Bleeding after sex...

So my boyfriend and I had sex in the morning we been trying for over a year and Soo after we had sex I wen to the bathroom to go pee and when I whipped on the toilet paper was blood and had a very faint cramp but barely knew it was therw well I thought I got my period since I haven't had one since Feb I'm irregular so I went to hope in the shower and I stopped bleeding ... It won't be the first time this has happened.... And I started to think I had a miscarriage at a early stage.... Have any one experienced this before