So my cycle is slightly irregular but for the most part it is always around 30-31 days long. We have been ttc for one and half years. Today is currently my 25 day in my cycle and I woke up to have dark brown almost black bleeding. Had to where a liner all day.  I normally spot a day or two before my period but this is a week before I'm due. We are about to start fertility treatments next month.  Does anyone know why I would be bleeding like this?