Pregnant or not?

on 6/8/08 i had a funny period started bleeding heavy then went away then started agin, then turned into spotting. My boyfriend came into town on the 21st of june, we have been having unprotected sex everyday twice a day.. then 7/3/08 i have cramps then start bleeding like i was going to have a period which just turned into spotting for the day. so for about 2 days just light spotting not even enough to fill a panty liner. sorry to sound gross but we would even have sex while i was spotting but he would pull out then put it right back in. now im having no appetite, feeling a lil down, slight cramps in my lower abd, and lil back pain.. please help me understand whats going on??