I am 19 years old, i am on birth control and i have sex without a condom on a regular basis. I am supposed to get my period this week but yesterday i started bleeding very dark blood, it has a lot of clots in it. It has some tints of like light red, I am sorry for the details, i just want to be thourough. Anyways, it is continueing into today. The last week and a half or so i have had very sore breasts, is this implementation bleeding and am i pregnant?