I'm afraid I can't remember the exact levels, but, like you, I was told that, given the hcg levels, they should have been able to see a sac, yolk sac and fetal pole but all they could see was a sac measuring small for my dates and hcg levels.
What have they suggested? Are you going to have a repeat scan?
Can you have a private scan? I know how you feel about not being able to think of anything else ... I eventually went for a private scan as I couldn't wait the three weeks the nhs suggested.
Diarrhea is a v normal pregnancy symptom I think so don't worry about that. If they suspected an ectopic, I think they would have told you about it so you could keep alert to the symptoms.
The other thing to think about is that you could have ovulated later than normal and / or your LO could have taken a long time to implant ... They can take anywhere between four and twelve days so thats a huge variation so early on. (I know this from having gone totally neurotic during my experience!).
I would tell you to relax until your next scan but I know that's impossible. All I would say is try to get another scan as soon as you can to see how things are going. Even a day or two can make a huge difference at this stage; I went from the second nhs scan leading the sonographer talking to me about 'ways to end the retention of the failed pregnancy' to seeing a heartbeat in 18 hrs.
I am sorry I don't know more about the hcg levels ... I will see if I can find my notes and get back to you!
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