Thanks everyone. Sadly I'm even more worried today, I think I may go to the GP on Monday, although not sure what he will do? Maybe refer me to EPU or do bloods? The lines on my Internet cheaply tests have been all over the place, lighter, darker, lighter, darker etc although that could obviously be because they are cheap and nasty. However, I also got 2-3 weeks on a digi last Friday and now 8 days later it still says 2-3. From what I understand your HCG needs to be 200 to get a 2-3 result and 2000 to get a 3+, so really it should have gone up by now, although I know I ovulated on CD 18.
Thanks so much for the reassurance that I am not the only one like this.
countmyblessings congratulations on getting to 36 weeks! All good from there hopefully! 
elsabel I don't mind paying for a private scan at all and if I get that far then I think that's what I'm going to do.
thefalconmistress (please tell me you actually have falcons? How cool would that be?!
) I have spoken to the EPU and she told me they don't see you just if you're worried, even if you've had early losses before or are high risk, she also lectured me about my GP giving my clexane, saying the haematologist should have given me it, which is obviously all very well if I could get a flipping appointment with them! I was in a different area before, but my haematologist there was amazing and referred me to the EPU right away.
I would happily pay privately for bloods to be done too, but I have no idea where to get it done, there doesn't seem to be anywhere in this area. I think I've resigned myself to a miscarriage now anyway, although I just wish it would happen. [Sad] Anything other than that will be a bonus.