My boyfriend and I recently had unprotected sex on 1/17 only lasted about 15 seconds I know we shouldn't have done it. He didn't cm inside me and I didn't give him a hand Job before hand it just happened. I took a plan b on 1/18 just in case my period should have started on 1/19 it is not 1/22 and idk if I should be worried. If There is a chance I'm pregnant or it's just late from stressing. Please help