i'm 15, me and my boyfriend have been together for nearly 10 months and we decided to have sex on valentine's day, we used a condom and he pulled out before ejaculating but the condom slipped down a few times while we were having sex but he pulled it back down straight away, it's been about 2 weeks and i'm starting to feel sick and have been for the past few days (i'm supposed to start my period any day now) could i be pregnant? i'm really paranoid.