bleeding durning sex and wasn't my first time

okay so me and boyfriend where having sex and it defiantly wasn't our first but it felt a little.. different. well we stopped because it started hurting  just a little well we start looking and there is blood on the bed and so we start looking at ourselves and he has blood on his penis and Im bleeding a lot. well my period is supposed to start Monday so I just thought it was that and so I put a tampon in well hours go by and I go to change my tampon but there is no blood I figure it's just really light well I go to change abother one and the same thing happened. no blood. I'm kinda freaked out honestly had this happened to anyone?