I'm 12 weeks pregnant, I had sex with this guy on the 12th of aug and the other guy the 29th of aug. I wanna know who could be my I don't remember my last period

Without . Without knowing when your last period was, it's difficult to tell who may have gotten you pregnant. Timing things from the last period is the most accurate way of dating a pregnancy. Ultrasounds and measurements can give an approximation, but they may be off by a few weeks which doesn't help you in your situation. You should talk with your ob/gyne doctor. Ask how they were able to time your due date and how accurate do they think it is. Since they have all of your information, they may be able to give you a better idea of whose baby he/she is. Good luck!