What Causes Vaginal Bleeding After Sexual Intercourse?

Hi Christy. I'm on yaz I have been for years.. The generic finally came out and it is not affecting me the same way. I have been on the generic for about 3 months now and after I was done with my period last period and started my new pack it stopped. But then a few days later I had sex and there was blood when I went to the bathroom after wards. Then last night I had sex, which was a few days after the first time I saw blood, and then this morning when I went to the bathroom there was blood again. The sex wasnt very rough at all where I should bleed from it and there was no blood during sex. I was looking on web md and it said to put a tampon in and take it back out to see if the blood is in the urine or not and there was blood on the tampon so its not in my urine. What else can this be from?