Miscarriage question πŸ˜₯πŸ˜₯

So Wednesday I had my follow up ultrasound that showed my baby stopped growing and there was not a heartbeat πŸ˜₯πŸ˜₯ my HCG levels also started to drop. My doctor told me to stop taking my progesterone so my question is my last pill was Tuesday when will my body start to actually miscarry?