unprotected sex

So I've been having a LOT of sex lately. for two-three weeks straight almost everyday sometimes up to 6 times a day. problem is our birth control method is withdrawal.. he never actually came in me but pre cum exists. and I know it's like a small chance of getting pregnant from that but I'm really scared. I'm 3 days late to my period and I'm NEVER late. what do you guys think I should do?