I am currently 14 weeks and 2 days pregnant I have been told my due date is 25th of December (Christmas Day!) which the midwife tells me I conceived around the 20th of March! Me and my partner went on a break and I ended up sleeping with someone else on the 18th! I then slept with my partner on the 20th and I'm now left very confused and worried! I contacted the other bloke he assured me he didn't cum and as far as I'm aware he didn't but obviously you can get pre cum and I can't be a 100% he didn't as I was very drunk! i also had a period since only one and not sure on dates of thosePlease someone help me as I don't know what to do!
Based on your due date your last period would have started around the 20th of May so you didn't conceive then. You wouldn't ovulate until between May 31 - June 4.
Doctors base due dates on your LMP. They add 40 weeks to it. It is NOT when you conceived, it's when your period started. You would have conceived about 2 weeks later.
Likely your partner is the father.