unprotected sex

I am 18 and my boyfriend and I sex with out using protection and I am not any birth control. he told me he pulled out before he came and it was all over my down stairs region. The time we had sex was my first time and I took plan b after two days later and that same day I took it we had sex twice with out protection and I am freaking out because I don't want to get pregnant. I don't know what to do.