I have had my period about 2 weeks ago and yesterday I got a what I thought was a spot bleeding that was gone directly after I saw the spotting and today it came back and it is very dark brown thickish blood and its coming heavy. I have been having unprotected sex the last year and a half with my boyfriend using the (pull out) theory. It has never happend to me before and I am a little stressed. Can someone help me with some ideas of what it could be please.