I am 11 weeks pregnant and was told I had an "impending miscarriage." How long does a miscarriage usually take

I am so sorry for your loss. I had a missed miscarriage in January. I know the baby's heart stopped within a week (it was slow at my ultrasound, so our doctor told us is would stop) We came back a week later, and there was no heart beat. I had no pain or bleeding. My doctor said our bodis can go into a vicious cycle of rising and falling levels of progresterone, the hormone that sustains pregnancy. A drop causes the uterine lining to shed. But in a missed miscarriage, the body knows something is still there, to the levels drop and then spike again. It sounded awlful. Because we wanted to start trying again soon, we elected to have a DC.