So.. Yesterday.. My Bf And I Had.. S*x.. My First

So.. yesterday.. my bf and I had.. s*x.. my first time.. I'm worried if i could be pregnant or not.. we didn't use protection.. I know that was a dumb move... but he didn't c*m(ejaculate) in me.. im not ovulating.. its a low chance of pregnancy.. and my period is supposedly coming in four days.. please help ease my worries..