I'm pretty sure the figures are correct and that I have miscarried. According to the scan last week, I was only 5 weeks (no fetal pole, just a yolk and a sac). Even if I was hwere I thought I should be, I owuld only by 8 weeks.
And it is only after 8 weeks that the elvels start to plateau and then declin.
So yes, there is a tiny chance that the results are misleading. That is why I iwll still be going for my scan next Tuesday.
But for me, the clincher is that for the last couple of week, I haven't "felt" pregnant. No extra loo trips, no excessive tiredness (both of which I did epxerience with ds), no extra discharge (tmi!) and definitely no thickening of waist (or, as my dh so delicately puts it, no "rounding" of my bum!). I am still in the skinniest of my trousers.
I'm human, so I won't totally give up hope until I've seen the scan next Tuesday, but essentially, I now expect the worst.