I have two due dates 9/25 9/22. my ultrasound read 9/25 is my due date. lmp say 9/22. i had sex twice 12/11 & 12/27 which day did i get pregnant?

Probably 12/27: If you became pregnant on 12/27 your due date should be on 9/18 (it is possible you did not become pregnant until 2 or 3 days later which would bring it up to around 9/21). If you became pregnant on 12/11 the due date would be on 9/2. So 12/27 seems much more likely. By the way, only about 1 in 30 babies are born on their due date, but almost all are born within 2 weeks of the due date.