I think I know the moment it happened.

I was doing the side plank at a yoga class when I felt something in my pelvic area. Not a pain exactly, but a discomfort that was deeper than usual.

I didn't give it much thought though. I've always struggled with that pose anyway.

That was in April.

I continued with yoga two to three times a week, relishing the stretches and challenging poses. My lower back, in particular, is stiff and painful when I wake up and yoga loosens me up.

In June, I went on a holiday to Hong Kong and did some heavy duty shopping. I paid for it - with my back. After a day of walking, the ache in my lower back was unbearable. I had to rush back to the hotel to soak in a hot tub.

Soon after, another problem appeared - this time, a dull, relentless ache around my right hip which wouldn't go away.

I tried heat pads and when that didn't work, ice packs. I slapped on plasters and analgesic rubs.

The office doctor couldn't tell what was wrong because my hips and legs were working fine. I could squat, I could jump. She gave me painkillers and they helped for a while. But the ache returned when I stopped taking them.

Earlier this month, I finally had enough and went to see a hip specialist. He got me to describe my discomfort and exercise history, examined me and concluded that I was suffering from sacroiliac joint strain.

The sacroiliac (SI) joints - one on either side of the body - connect the sacrum with the pelvis (iliac crest). Stress at the joints can be caused by childbirth, an accident, sudden movements and poor standing, sitting and sleeping habits. Pain there could also indicate serious illnesses like rheumatoid arthritis and ankylosing spondylitis.

The doctor said too much yoga probably led to my strain. But to rule out other causes, he got me to go for an X-ray and a blood test.

I went to get these done and returned to his clinic with my X-rays.

That was when I got another piece of bad news - I've got lumbar scoliosis, which is curvature of the lower spine. The X-ray looked scary with the last part of my spine clearly slanted to one side. The doctor - who looked alarmed - said the discs in my spine were also twisted.

He measured the curve. It was 20 degrees, which he said wasn't that serious - thankfully.

One week later, results of my blood test came back. I tested negative for indicators of rheumatoid arthritis and ankylosing spondylitis. The other readings were within the normal range.

The doctor said my lower back and hip pain were probably due to the SI joint strain as well as scoliosis. The best thing I could do for the strain was to rest. There wasn't much I could do about the scoliosis. If I wanted to exercise, I should swim, he said.

If I sound matter-of-fact about my hip and back woes, I actually wasn't. Truth be told, I've been quite a nervous wreck these past few months.

When it comes to my health, I am often over-anxious, pessimistic and convinced the worst will happen.

I blame it on the Internet.

There's so much information about diseases, not only from websites like webMD and Mayo Clinic but everywhere from women's to fitness, news and entertainment sites.

Symptoms, causes and treatments are explained in layman's terms, making it easy for anyone to self-diagnose, never mind that your knowledge is half-baked. There are also thousands of online patient forums where you can share your experiences on anything from haemorrhoids to haemochromatosis.

All this information can make your imagination run wild.

When I got the hip pain, I naturally turned to the Internet and found out that the causes could be arthritis, hip fractures, tendinitis and bursitis, hernia and gynaecological problems.

Maybe because I'm at the age when women have more "female" issues, I zoomed in on the last cause.

I started worrying that there was a cyst growing inside me, impinging on my nerves. In my mind's eye, I could even picture the cyst, red, nasty-looking, throbbing and ever- growing. There was a real drama playing in my head and the more literature I read on the Web, the more worried I got.

Later, when the doctor told me I probably had an SI injury, I went on another Googling binge and read everything I could about sacroiliac joints, especially SI injuries caused by yoga. After a dozen or so articles, I even fancied myself a mini-expert on the joint - preposterous, of course.

Then when my blood test results came back, I researched what the readings meant and whether those on the low or high side of the normal range indicated there was something seriously wrong with me.

There is a popular term that has emerged for people like me - cyberchondria. It is derived from the words cyber and hypochondria and used to describe how some people excessively use Internet health sites which escalate their medical anxieties.

In 2008, two Microsoft researchers, Ryen White and Eric Horvitz, did a fascinating study on this behaviour. They found that Internet queries of common health complaints could escalate to queries on more serious illnesses. These searches could continue in the days and weeks that followed, even disrupting non-health-related search activities.

The researchers also surveyed 515 people and found that overall, people report to having a low level of health anxiety.

However, one in five say they frequently find their medical anxieties escalating after searching the Internet and two in five say interactions with the Web increase medical anxiety.

Whether or not a person gets freaked out depends on his general anxiety level and predisposition to anxiety.

The researchers also found that when someone types in a query for relatively common symptoms, Web search engines may retrieve pages that contain alarming content that can alert them to the possibility of serious illnesses, without providing information about how likely one is to get the serious condition.

This may occur for several reasons, they said, "including the relatively large quantity of Web content describing serious illnesses compared to benign conditions, and the potential use of ranking algorithms based on historical click-through data".

Not everything on the Internet is suspect, of course.

The Web can be a valuable tool in understanding medical conditions.

When the Singapore General Hospital hepatitis C outbreak story broke last week, for example, one could get useful information about the different types of hepatitis.

What's important, I suppose, is to make sure the medical information you get is reliable and you get it verified by a doctor.

Readers should ask who's responsible for the information, who funds the site, what its purpose is, whether the information is supported and reviewed, who is on its editorial board and how current the material is.

I calmed down somewhat after I got my blood test results.

I have since gone to see a rehabilitation training specialist. He said that my right ankle joint lacks mobility, which causes my foot to sway outwards when I walk, which in turn overuses some hip muscles.

I also have trendelenburg gait, causing the right side of my spine to collapse, impinging on nerves and resulting in referred pain.

I didn't understand half of what he said and when I got home from my session, my instinct was to go to my iPad and start Googling what he said.

I stopped myself in time.

If I come down with a serious illness, it will make itself known, no worries about that. Meanwhile, there is no point pre-empting it by cyber-diagnosing myself and scaring myself silly.

A little knowledge is a dangerous thing, not to mention how it can unnecessarily add to anxiety levels.

Instead, I took out the little balls I was given and started doing the ankle exercises I had been told to do.

I think it was a far better use of my time.

•Follow Sumiko Tan on Twitter @STsumikotan