I'm sorry all this waiting has been so scary. I definitely know how that feels. *hugs* If you are hearing the baby on the doppler I think the chances are very low that you'll suddenly have a problem with the heartbeat at your Dr. appointment. Even now that I can finally find my baby's hb on doppler (only in the last two weeks), it still takes me a good 5-10 minutes to find it every time, and it's always so faint... and yet when I go in for my appointments the baby always looks great. I've kind of come to think that despite all my fears and worries, this little one is stronger than I've been giving it credit for.
Lots of good wishes to you for your rescheduled appointment! I'm looking forward to hearing how it goes.