Strange bleeding

I have PCOS. I have not had a natural period in years! When I got pregnant with my son, it was after a year of no menstrual cycle. He is five and I had one naturally in December of 2012. The rest have been via provera. Yesterday, I noticed a dark brown mucous like discharge after I went to the potty. It is also a dark red sometimes. It kinda looks clotty in the toilet. It has continued through today. The odd thing is it's not heavy. Does not stain my underwear, and some chunks are in the toilet after I use the restroom. I only see the color change on the toilet paper after I pee. My husband and I have been trying to have another baby. No luck. I haven't taken anything in a while, just trying to be more healthy. We have not been preventing pregnancy but have stopped jumping through hoops after failed fertility treatment. I am cramping some, have noticed a change in appetite, and feel a little nausea. I tested and got a negative. Any tips or advice?