"hi all- hoping to impart some peace of mind to anyone waiting for it to work. my boyfriend &amp; i had sex on may 4th, last day of my period. he finished in a condom, then later went back inside me unprotected. he didn&#039;t finish the 2nd time, but i wanted to be extra careful. i took plan b ~18 hours later. i had a withdrawal bleed five days later (may 11-12th) that lasted 2 days, and was supposed to get my period on the 27th- it came today, 6 days late on june 1st (stress/jetlag may be to blame). some bad side effects- depression, mood swings, thick white discharge, headaches, fatigue. 
i&#039;d urge you to keep track of your cycle for added reassurance in these situations (know your fertile window, etc.). sending peace &amp; patience &amp; don&#039;t be scared!"