Plan b

My and my boyfriend has sex today. We used a condom but it broke. I am not on any form of birth control besides the condom. It’s the last day of my period and I just have a little red discharge. eve says I only have a 1% chance of getting pregnant.

I would like to take plan b, but I have heard that it messes up your body. I was wondering if that is true and also if I should even take plan b. I am under age and my mom does not know that I have had sex.

If you guys could just tell me your thoughts and give me advice, that will be greatly appreciated. Thanks!