HELP PLEASEEE

Okay so I only had sex but not really because it didn’t go all the way in and that been about a year ago but I had sex sex fr the other night and this morning and after we was finish I’ll go to the bathroom and pee and it will be blood but not a lot like spotting and this morning when we did it he notice it and I just told him my cycle about to start which was a lie I was just kind of embarrassed. But why did I lightly bleed after sex and I’m for sure thought my cherry pop they first time I attempt to have sex because I remember so I’m just confused on why I lightly bleed after sex???