"on december 13th there was an incident and i had to take plan b. i took the pill about 30-40 minutes after the incident because the sooner you take it the more effective it will be. i waited and waited for my period which was supposed to come around dec. 25 but never came. today i took 3 tests and they all came out positive. i&#039;m not saying the plan b does not work, but i am posting my experience as a warning to those who take it without knowing their risks. plan b make work for some. many say that for those who it didn&#039;t work for is because they didn&#039;t take it within 72 hours. i took it right away and it wasn&#039;t effective."