My hcg levels still haven't dropped after miscarriage...

Kortney
I went to the hospital on the 8th due to bleeding at 7weeks and found out that I was having miscarriage. They took my hcg levels and they were at 186.. Last Monday I had my hcg levels tested again and they only dropped to 155. I am still bleeding and cramping. Is this normal? What happens if my hcg levels don't drop back down to 0?