Are u serious? Why you asking a forum for help? You knew what you was doing when you was having unprotected sex with two different guys. When the baby is born the EX should take a paternity test since he should know that u had a boyfriend he was the one who was the "secret" so having a paternity test should be done first...and if it is not the ex baby then you know its your current BF baby and he will never ever know about it, u can live like nothing happen
If you had a period, you weren't pregnant previously. It's impossible for a female to be pregnant and have a period. Regardless of if you "felt" pregnant.
You have no choice, you have to have paternity testing done. The dates are too close together. Does your partner know that you were unfaithful? If not, I would definitely start talking to him about it, and that it's very possible the child isn't his.