PLEASE HELP: pregnant or not?

i’m 9 days late. i had unprotected sex 3 times the night before i was supposed to start my period. he pulled out. i am usually not late. however, about two months ago i took a plan B. i had my period after that but is it possible the plan B could mess up my second period? orrrr is there a good chance i am pregnant? when can i find out for sure?