Levonorgestrel
"I had to take Plan B 2 times and I'm also 168, slightly above the "weight limit". I should've learned the first time but of course, didn't think it was going to happen again.  I didn't get any side effects other than swollen boobs the first time and began spotting a week later for 2 days before starting my period. The second time, I immediately got intense stomach cramping after taking it and then fell asleep for 3 hours. I spent the next 9 days stressed & crying, thinking my period wouldn't come. I had cramping in what felt like my ovaries every night, so I'd think my period was coming, it didn't. On the 9th day, a full on period. This a very necessary medication but please, don't put yourself in a situation where you'd have to take it."