On the 12th my boyfriend and I were together and things got intimate. My ovulation day is supposedly the 18th. He was playing with his junk in the hot tub and then touching me, and then we got out and things progressed. Our genetalia was rubbing on each other and for a split second his penis entered my vagina. Barely nothing but his tip did go in me. He never ejaculated fully but throughout all of what we did I'm really scared of precum. Should I take Plan B? I would be able to take it tomorrow morning. Would it still work? Is it worth the money?