my boyfriend came over on Thursday August 6th, we had sex twice that night. at first I didn't think he finished, until I felt him tense up and then I was like I hope he didn't. well, Saturday night we were going to sleep, and he done it again but this time he told me he came in me. Sunday morning which is August 9th. we had sex that morning and he done it again. so four times all together. I took plan b Sunday morning sometime around 12 maybe. But will it still be effective on the fourth day? or will I get pregnant?