If you have the ultrasound, you should be able to look on the face of it and see a date, along with the 7 weeks 5 days GA figure. Is that where you got September 12? I hate to give advice on these things and then have the person come back and say, "But that can't be right, because of the ultrasound I had on August 22" or whatever.
Anyway, the ultrasound from September (whether September 1 or 12) seems to indicate that you got pregnant from your boyfriend, if the only time you had sex with anyone else was August 18. If you got pregnant that late, you'd only be at about 12 weeks 5 days pregnant now.
im sorry, I meant sept 12th
I am pretty sure my ultrasound was sept 1st if I remember correctly.
I apologize it wasn't clear, I meant I got a home pregnancy test two weeks after the one night stand, then two weeks after the home pregnancy test I had an ultrasound. I cant remember those exact dates.
Can you be more specific about what 2 weeks later followed by 2 weeks after means? In other words, you had a home pregnancy test two weeks after you had sex on August 18. Does that mean, September 1? And then "2 weeks after," you got an ultrasound that said 7 weeks 5 days GA. Was it two weeks after the September 1 test or two weeks after the sex on August 18?
You're right that things point to your boyfriend, and the simplest thing to do is wait for results on your DDC test. I can't check the logic of the story, not knowing on what calendar date you got 7 weeks 5 days.