I had sex with my boyfriend unprotected on nov.27. Then I had protected sex with another guy on Dec.6 . Now I'm pregnant and my due date is Aug24 and I think my conception date was around Dec 3. Which guy is my baby's father?

Yea, you conception date by the doc's assumptions would be Dec 2 or 3 but that's just a guess by how big your measuring, when your last menstrual period was, etc. I would say that you have a higher chance of it being your boyfriend since it was unprotected but you never know what could happen.

The one whose DNA matches the baby's after the baby is born.