I need help , ultrasound/lmp question
My lmp was June,24th 2010 ,I have regular 28 day cycles. I am 13 weeks pregnant today actually , I have had three early ultrasounds and the dates given by the ultrasounds all match up exactly to my lmp on June 24th, here is my problem , on June 14h me and my boyfriend were on a break and I had sex with my ex I then got what I think was my period on June 24th. And me and my current boyfriend worked things out , so I guess you can say sex with the ex on the 14th was a one night stand. So me and my current boyfriend wanted to coneive, all my ultrasounds match up to my lmp of June 24th . So if I am 13 weeks pregnant now , by ultrasound and lmp does that mean I conceived 13 weeks ago? Or are they going by gestational age(lmp).. (which by gestational age calculators say I conceived between July 6-9th) ) is there ANY possible way the my ex is the father? Or is my boyfriend the father? How do ultrasounds measure.. by gestational age? Did I get pregnant after my period! Please help
Comment on DoulaLC's post
Thank you. If the other man was the father the ultrasound would measure gestational age about three weeks greater right? Because it would measure by the lmp BEFore the one on June 24th? So to ease my mind , you think the current boyfriend almost sure