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Hi Guys. So I am 21 years old and my boyfriend and I had sex for the first time on either the 5th of March, 2016. We used a condom and it was my first time (he had experience before). However, while we were having sex, we discovered i was on my period. Regardless we decided to have period sex. Whenever he wanted to "do it" he make sure he do on my chest and not inside me or anywhere near my vagina. And every time we had sex, we change condoms to avoid any breaking. I was expecting my period to come on March 7th, but now I am four days late.  Just yesterday i took a pregnacy text (First response) and I got a negative. but I am scared that I may be pregnant. I don't understand what we did that might make that mistake. I am freaing out. I don't know if it is my stress, diet or whatever. I guess another thing ot have is that we make out in the showe, but we make sure his penis does not touch my in the V area. 
 

I am scared.. please tell me what i should do...  thank you