Levonorgestrel
"I had unprotected sex and I took the pill 30 hours later. I felt a bit drowsy within the first few hours, however over the next two weeks I experienced cramping. The cramps were really bad.10 days after taking the pill my breasts completely swelled. My nipples were always hard and the pain was unbearable. I was convinced I was pregnant. The cramps continued and I was experiencing back pain. Then the pain in my breasts finally began to subside and I got my period the next day, exactly when I was supposed to. It was a little bit heavier than usual but I've never been happier to be on my period. The pill messes up your body due to increase of hormones. I've read it makes you feel exactly as pregnant women do so don't panic over the symptoms!"