I had unprotected sex on July 24 (but on the pill because i started a new pack, and he did not cum in me) the day after my period ended. This month I have been under extreme stress, started a new workout program, missed a pill this past friday but took two on this past saturday, and have been using an over the counter hydrocortisone cream for a rash. The past two days theres been brown semi heavy discharge. Im concerned is this breakthrough bleeding or possible implantation bleeding?