Help. Young and worried

Me and my boyfriend had sex for the first time and he didn't actually ejaculate inside of me but he put his bare penis inside and I'm worried about Precum?

I took the Levonelle plan B tablet 44hours later (you can take it up to 72 hours after) but I'm extremely worried. I've had no bleeding but I have had mild cramps, I'm worried that it won't have prevented a pregnancy and I don't know what I'm going to do.

What are my options if I'm pregnant? I really can't have a baby.