emergency contraception
"I had unprotected sex the night of the day I apparently was ovulating (didn’t “know”, didn’t check my period calendar. the period calendar is pretty accurate with keeping track). I took Plan B within 10-12 hours (the next morning). My period was expected to come 2 weeks from that day, and I got my period 3 days before it was expected to come. Plan B is definitely something I would recommend if you are worried about getting pregnant"