could I be pregnant

I am 16, me and my boyfriend were just messing around on December 27 and he didn't really stick it in or anything And then the next day I got my period but it was very light and lasted 3 days, went away, and then came back randomly for not even an hour. 2 weeks before my expected period I started getting symptoms before you get periods like tender breasts and bloating and pain, but it has been a day and I still haven't gotten my period. Could I be pregnant? I'm really scared and don't think I could be but I need reassurance