Implantation bleeding? TMI-pic

I have has this brown discharge for 3 days now. I'm not really sure what it is. It is only when I wipe. Today it doesn't seem as much as it has been. I am on birth control so we aren't ttc right now. I have gotten pregnant on birth control once though, sadly that ended in a miscarriage. I still have 3 days till my period is supposed to be here. So this started approximately a week before my period is supposed to start. Anyone have any ideas of what this could be? Any thoughts/help would be appreciated:)