"this works. i had no doubt in my mind about that! so basically my boyfriend and i are always using protection but about 5 days ago that condom slipped off. about 12 hours later we bought plan b and i took it. i was due for my period like 2 days after but it never came. after what felt like the longest 5 days ever, i finally got it today! so don&#039;t worry, periods are often delayed by this. anyways, this saved our lives. whew!"