unfortunately these things aren't always text book... sometimes you just have to wait and see how it turns out.. I know it is hard..
Best of luck to you..
Are they doing a vaginal ultrasound? When do you return to see your fertility doc? Are they monitoring your progesterone levels? What time frame are we talking here?
You should see a sac at 5 weeks, *most* folks can detect a heartbeat around 6 weeks from LMP or 2-3 weeks past ovulation but sometimes it takes longer for that. On a vaginal ultrasound (which is definitely better), you should start seeing a formation around 6-7 weeks LMP with a heartbeat. But as Tanker Chic says, some pregnancies aren't textbook.
I hope you are lucky and have a keeper!
Thanks for the support. I have another US on Februaury 14th. A lively little heartbeat would be a lovely gift. The waiting is just too hard.