BFN after miscarriage

For those that took cytotec or mc naturally, how long did it take before you were able to get a negative pregnancy test? I had my miscarriage October 1, and my tests are still bright and positive. I go back to my doctor Monday but just wondering what others experiences were. I feel like I'll be able to move on easier if I could just know my hcg levels are down. This is so frustrating to still be pregnant.