"this works! i&#039;m writing this because, for two weeks after taking this i stressed about it being effective. i&#039;m 21, in college, 5&#039;1 and 110 pounds. i don&#039;t take birth control because i am not usually sexually active. long story short, i had a risky one night stand, unprotected. (stupid, irresponsible) i know. i took plan b one step at around 6:30 the next evening, around 15 hours later. i was especially worried because this was right around ovulation time. i had few side effects. day 1 was at night, gave me a slight headache and made me depressed. day 2 i felt fine all day but had a few instances of dizziness. about a week in i had mild cramps and slightly sore breasts. now, two weeks later, my period came, right on time."