Thank you for all your replies.
Thought I would post an update.. sorry, a little long...
So I finally got my blood test at 5 weeks, and found my HCG level was at 150, which was quite low. I was very worried about the level, but doctors and family told me not to worry, and that I was being too paranoid!... so I let it go..
During the weekend (nearly 8 weeks pregnant), I started getting intense lower back/bum pains. I thought this was just hormone levels kicking in, and it made me feel happy to feel some 'pregnancy' symptoms, since I had been feeling nothing. I started bleeding large clots on easter Sunday, and the pains continued. I had to wait till Monday to go to the doctors where I had blood test done for HCG level. Tuesday (8 weeks pregnant) I got my HCG level results: 186. I was then sent for internal ultrasound where they found nothing my uterus. The lining of my uterus was very thin; indicating nothing there in the first place (i.e. not a miscarriage). They suspected it was an ectopic pregnancy so they sent me straight to emergency at Royal Womens Hospital. Anyway, it was a very long day at the hospital but to cut it short I was given an injection on Methotrexate and sent home.
I have to return this Sat, then Tues to ensure my HCG levels are decreasing (cross fingers!). I am very lucky that I did not have to have surgery to remove my tube and that my levels were low enough for the injection.
I just want to post my story so that it will make other women aware that if you do have low HCG levels (lower that normal statistics) to please DEMAND for subsequent blood tests every 2 to 3 days to ensure that they are doubling. Even if your doctor disagrees, I would go to see another doctor. I am sure that a majority of the time it may be ok, although you may have the chance of catching an ectopic pregnancy early on, and therefore possibly saving your fallopian tube.
This was going to be my first pregnancy. My biggest fear when we started to try and conceive was having an ectopic pregnancy... and it happened. No idea why it has happened to me as I did not fall under any of the risk factors for an ectopic pregnancy. Although now I do: "Have had previous ectopic pregnancies". I will now have to wait at least 3 months before tying to conceive again du to the injection. Although, my biggest fear once again is that I will have another ectopic pregnancy..