emergency contraception
"My girlfriend took Plan-B 13 hours after we had unprotected sex. 
It was our first time and, to get better, she was in her fertile days. I didn't finish in her but we're freaking out anyway. 
The next few days were horrible, I was googling all the things about levonorgestrel and feeling a lot of anxiety. Even the fact that she wasn't experiencing any side-effects made me more nervous. However, about a week later the period finally came. 
Plan-B really works, it's all about taking it ASAP and trying to stay calm."