My boyfriend and I had unprotected sex about 10times for the last 2 months and lately I've been having a sharp pain in my abdomen like if it was cramps but sharper, as if someone was poking me with a knife on the inside. I knew it wasn't my period coming because they stared a day or two after my last periode. Him and I had done it three more times sense it started and nothing happened untile the secone time I got home and went to the restroom and was bleeding. I just thought mabie he ripped my himey because it stopped in an hour but then last night when he pulled out I was bleeding as if I stared my period and both of us wondered if I did but it stopped and then started and stopped again. When I woke up this morning I wasn't bleeding but later around 150 I was.. What does this mean?

Ow! Could be you have a polyp or some kind of growth on/near your cervix and having sex irritates it, makes it bleed a bit for a short while. It could be a bunch of different things.
But you really need to go to a doctor, to have this checked out and also to get on birth control. If you don't have money, try looking up the nearest planned parenthood. They are either cheap or free.