Brown discharge 😣😣

I am taking 400mg progesterone pessaries daily. cyclogest. Last night when I went to the toilet I noticed I had tan colour discharge. When I wiped you could see it on the toilet paper... I also had a bit of crampiness but that eased off. I woke this morning and there was nothing. No brown when i wiped. I still have sore boobs and so tired. However when I inserted the pessary there was the tan colour discharge again. Also with this was bit of darker brown going through it. like dark brown spots is the only way I can describe it. I've had lower back ache which seems to be better when I walk and move. it's noticeable when I sit. it's not excruciating but it's that niggly pain... I've not since had it again. But I'm scared it's a sign of miscarriage. Anyone got any advice.