I'm 16 and me and my boyfriend usually use a condom but for the past month I took a chance and we had sex 5 times without a condom, after the third time I had really bad pain in my uterus and it hurt to pee it went away two days later and we had sex one last time 2 days b4 my period was due (each time we used the pull out method) and I still had my period on time, y is that?