Been Bleeding and having black/brown charge on and off again for 3 weeks, I am on Amethia, second month since switching birth control, is this normal? Usually my bf and I have sex with a condom but 2 weeks ago we used pull out method (yes I know not effective), just wondering what is up with this dark red bleeding for maybe one day then blackish/brown discharge on and off again. Usually doesnt even use up 1 tampon. Help, should I call my dr? Could it be pregnancy or something else?