I need help. I'm 29 weeks pregnant. My first day of my last period was September 26 2014. My boyfriend and I slept together lots but we broke up for a week and I slept with someone else on the 21st. Can someone please help me out

There actually isn't a question here, but I'll assume that you are asking who the potential father is. If you were sexually active with both men a week apart, there really isn't a way to tell, and you'll have to seek genetic testing after your baby is born. Sperm can stay alive for days inside your body, with the overlap you are describing, either man could have fathered your child. If this is not the question you are seeking an answer to, please update with the information you are looking for.

If you are 29 weeks, ultrasound apparently determined that you became pregnant after your last period. It would also be very unlikely for you to become pregnant just days before a period. Add to that the fact that you had a period after the sex on the 21st and you would be further along if you became pregnant from that encounter. All of that should ease your mind

If you want to make absolutely sure, you'll need to go with DNA testing as was mentioned.

What do you want help with? Determining paternity?

As DoulaC said, if you had a period after your encounter with on the 21st, then it is unlikely that partner is the father. But its not impossible. The only way to positively confirm paternity is with DNA testing after birth.

Gestational dating is a mathematical formula that contains room for error. While I do agree with the responses you have been given, a DNA test is the only way to know for certain.