a week ago, I tried to have sex with my boyfriend, he put the tip in, then I started to bleed, after a couple hours I was fine. 3 days later, I put a tampon in because I realized that there was still blood inside of me, I leaked through the tanpon. Yesterday, I woke up in the middle of the night and I bled through my pants, it happened for about 4 hours, and then today, I bled completely through again.. What is the cause of this? I don't understand what is going on and I'm scared..