Thanks for the advice guys, and yeah I'm pretty sure he didnt because it was literally SO quick and I've asked him about it numerous times. Also, when he and I were together we never really used condoms and he always knew when to pull out so that I never got pregnant. Another thing that I looked up was types of discharge when youre about to start ovulating and I'm pretty sure I ovulated on Nov. 26th because I remember going to the restroom because I felt moisture and the discharge matched the description of discharge that you get right before you start to ovulate, which makes me think that its more likely my bf's, but I just still get paranoid about it sometimes.
Oh, and my due date is also Aug. 20 and I know for a fact that I conceived on Nov. 30.
It's probably your boyfriend, but you should get a DNA test when the baby is born.
I'm sorry you are having such a hard time with this. As you know, the only sure way to know is by a paternity test once the baby is born. Off the bat, it is more likely that your boyfriend is the father based on what info you have provided however, are you certain your ex did not ejaculate inside you? In a hospitable environment, sperm can live for up to 5 days. If he did, then it is highly likely either man could be the father.