"i&#039;ve had to take plan b twice (well, technically the off-brand they have at my pharmacy), both times during or after ovulation. the first time i hardly experienced any side effects other than my period coming two days early, and i didn&#039;t get pregnant. the second time was a couple weeks ago after my boyfriend and i had been going at it, and when he pulled out to switch positions i heard him say &quot;...oh&quot; and he pulled the crumpled condom out of me. about 20 hours later i went and got plan b. i was nauseous and cramping the next day and had more cramps for three days leading up to my period but it came on time! the pill works, don&#039;t worry yourself."