I agree with clairemuir about calling the hospital to get the midwife number so that you can get some reassurance - they will be very sympathetic if you have had a miscarriage previously and they do understand how much we all worry - I had a major panic and sleepless night a few days back because I'd decided the baby wasn't moving any more - in fact when I calmed down in the morning I realised the baby actually was moving but just little faint movements that I was panicking so much I was ignoring... 20 week scan then showed very healthy bub.
We can't help freaking out when we find something to worry about, but I think from what I've read and from what everyone seems to be saying that it's normal for the early symptoms to go in second tri. I actually think it is the hardest time of all, between the disappearance of first tri symptoms and the time when you start to feel regular movements, cos there's just nothing to go on anymore symptomwise to reassure you. I'm sure you'll be ok, hang in there xxx