Please someone respond very important.

I'm 17 years old. I had intercourse around dec 23-27th ( not everyday but like 3x around there) with a condom and he pulled out and came in the condom. I got my period January 2nd 2019. I had cramps so bad the first day and was heavy. Don't remember how long it lasted I'd like to say 4 days. Now I check my period tracker and it says I'm 3-5 days late. 3 days on this app. Could I possibly be pregnant? I don't want to get a test done I'm scared because apparently I'm suppose to have my period by now and I hadn't. I also had my period early December.