Desperatly hoping that all is okay, I had a very similar experience with Poppy, sac with nothing happening in it, the pregnancy was called equivocal meaning it could go either way, my levels increased but not as good as expected, got another US at 7 weeks expecting to hear th eworst and there was a tiny bubba with a HB. Was'nt the end of my problems, but sooo worth it in the end, when I got my gorgeous little girl.

Good luck and thinking of you lots.