I'm a guy, questions about pregnancy.

My girlfriend and I started having sex in the beginning of February. We had unprotected sex on two separate occasions(one being earlier tonight), both of which I didn't ejaculate inside of her. The first time she took a Plan B pill, and this time we haven't decided if we're going to do anything. Do you think we were overreacting with the Plan B, or if we should use it again tomorrow?