Miscarried on 8/20 and still bleeding.

I lost my peanut on 8/20, completely passed everything within 4 hours, the ER did not see anything left over during the ultrasound. I had an HCG test on the 27th that registered 195.

I am still bleeding, it was very faint for about a week and has now gotten a bit heavier, moreso when I use the restroom. I took a PT this morning to see if my HCG was still registering and it came up negative.

When should I expect the bleeding to stop? He was 13 weeks. Is there any correlation to HCG levels dropping and the bleeding stopping?