pregnancy scare? help!

so my boyfriend and i were showering together doing anal (tmi, sorry!) and it accidentally slipped in my vagina for a second. there wasn't cum, i'm just worried about pre-cum getting me pregnant because he hadn't peed the last time he ejeculated. he said he wiped it all off before it happened so there was nothing on it when it slipped in. i was also on the last day of my period though so i'm just wondering the chances of pregnancy? please no rude comments, just needing serious help! thankss