HI Guys

I have been on cloud nine after finding out I was pregnant 2 weeks ago, and as I was on clomid my Ob wanted me to come in for an internal ultrasound at 5 weeks (today).

He said, yes I was pregnant, no it wasn't ectopic, yes he could see a gestational sac.
But...he said that he was slightly concerned becuase there was a blood clot behind the sac, and coudln't confirm a viable pregnancy for another couple of weeks.
I haven't had any spotting, pain and I don't have any pregnancy sypmtoms.

Has anyone had this before?
Will I miscarry?
I am really scared and want to know if there is anything I can do to make things OK.

Can anyone ease my mind???

Thanks

N