Please help me with paternity questions

[J123457]

I had sex on July 31st without a condom and then again on aug 4 with someone else  and I cant remember if I used a condom or not. I had my first ultra sound at 10 weeks pregnant and it said that my conception date was July 31st.Now at 28 weeks  pregnant my due date has changed by one day and is now saying that I concieved on aug. 1st. I ONLY had sex on those two days and then a month later i found out that I was pregnant, so it has to be one of those days. when did I concieve?  and  I know I can get a paternity test but I am trying to ease my mind now. Also i figure that it cant be the guy on aug 4 because why would the conception date be early. so i am wondering did I conceive on July 31?

[smjmekg]

They tell you when you conceived, but ON or AROUND that day...not that exact day. No one can tell you the exact day you conceived. Sperm can live inside your body up to 5 days, so if you had sex with a guy July 31 and Aug 4, the guy from July's sperm may have still been inside you and the Aug guy's sperm could have been in there too (since you don't know if you used a condom) SO either guy could be the father, sorry to say...but you definitely need a paternity test to know who the father is. There's no way to tell other than the test.

[penswriter]

the only way you're going to know is a paternity test.

[jrobertson20]

Well you don't necessarily conceive the day you had sex.  You may have ovulated the day after or so and that is when conception happened.  The dates are so close together it is hard to tell when you really conceived but from the dates they are giving you it sounds like it is the 1st guy....but dates can be wrong.  Hope everything works out well for you.