I too have a similar situation. By my LMP today I should be 7wks 5days pregnant. I had my HCG levels checked at 4wks and the first day HCG was 68 and Progesterone was 11.5 and 48 hours later HCG was 179 so they more than doubled. I also have been taking 200mg of progesterone a night.
I went this past Tuesday for my first full prenatal appt which according to my LMP I was 7wks and 3days. So my dr did a vaginal ultrasound (he does U.S. every visit and vaginal ones up until the 12th week), anyway he found the sacs and then found the peanut sized baby but said he didn't think he could see a heartbeat. A couple of times he thought he may have seen it and even had me hold my breath to make sure wasn't my pulse but said if what he saw was the baby's heartbeat then it was slow. He said by the ultrasound the baby measured 6wks and 5days. THEN he comes back in the room and says he wants me to come back in 3 days which is tomorrow and do another ultrasound. He says if he doesn't see a heartbeat then we need to discuss option of a D&C. But now after reading on here and alot of other sites I don't want to jump into a D&C. I had D&C 10 yrs ago for a blighted ovum and just don't want to go that route again. After reading everyone's stories on here I'm beginning to have a little more hope and faith that our story will have a happy ending. I have a 14yr old daughter and was told then I had a tilted uterus and hoping that is the reason for not seeing HB. Also I take heart medication for my heart condition that also lowers blood pressure so maybe it just lowered my baby's blood pressure enough that it makes it harder to see the tiny heart beating on the U.S. machine so early.
I pray to God that he will bless us with a healthy strong heart beating baby