A few days ago my boyfriend and I we're sexually active without a condom and he did finish in me. Now I know its too early to determined if I'm pregnant with a pregnancy test and my period isn't due for another week. Since then, I've felt period like contractions in my lower abdomen but a period doesn't follow. Today every time I sneeze, I feel a stabbing, sharp pain in my lower left abdomen... Could that be due to me getting pregnant or could it also be something else?