Doctor Plz Help Me. I'm Really Concerned About My Pregnancy.

Doctor plz help me. I'm really concerned about my pregnancy. I nd my bf were fooling in his room on 22 october 2015. We did not have sex. He just ejaculated near my vagina indeed very close to it but not inside it. There was no intercourse. Still for safety i took an ipill within 28 hours. I had my periods a week later i.e on 27 oct then in nov nd dec also i had periods lasting for 3-4 days. In nov my date was 24 nd in dec it was 27. But in january today is 27 nd i did not have periods. Really worried. Can i be pregnant even after having periods for two months after that act.? Plz help. This tension is killing me. If i'm not pregnant and i do not get periods this month then what should i do. Plz tell soon