last day of period stupid question

So my period started Monday at 3am and should go off Saturday. I can't really remember how my periods end because I have nothing to look forward to. But graduation is this Saturday and the guy who has given me the best sex EVER will be in town? I know for me keen I drink my period stops but is heavy the next day. Does that happen to anyone else? Should I be in the clear for after my festivies for graduation sex?