7 yrs ago I had sex with my ex-boyfriend,and after that I've never had sex with someone else.But I just had a boy friend few months ago.And last Friday that was April 11 and April 13 were just having sex.And after the sex my boy friend asking me,why did I have the blood after the sex. And when I used the rest room to pee,I saw the blood on the toilet bowl. What does it mean?I'm really worried, please respond when you receive my message as soon as possible thanks!