Curiousgeorgie, sorry to hear about your miscarriage.
I had a MMC at nearly 12 weeks, just before what would have been my first (nuchal) scan. Had breezed thru 2 previous pregnancies, and had felt very complacent - and VERY sick - so it was a real real shock.
I am now 32 weeks pregnant, and totally relate to what you're saying: every little twinge had me worried this time, every bit of discharge (sorry TMI!) had me running to the loo, scared it was bleeding :( But everything has been absolutely fine, touch wood, and I am getting ready for a home birth now baby has stopped being breech! :)
I think I held back from...getting excited about it until the 12 week scan this time , and was very superstitious about buying prams/ baby stuff this time, which I was not before. But on the other hand, have also really treasured this pregnancy, probably because this is the last time (am 39), and also because it feels so precious, and such a gift this time round, if that doesn't sound too Hallmark-card-y.
As other posters have said, a private scan (if EPU won't scan you) might reassure you, and I wish you all the best with this pregnancy.