Spotting after stopping progesterone??

TW: mention of spotting

I’m currently 12+5 weeks and have been weaning myself off my progesterone suppositories all week. I was taking 2/day, now I’m down to one at night. For the last 3 days I’ve have body aches and lower back pain, some cramping. Basically feel like my period is about to start. Then today noticed some light spotting.

Is this common when stopping progesterone? Has anyone else experienced something similar? We saw baby today, HR was 155bpm and was very active, so I have some relief there, but still curious.