Why is my miscarriage taking so long?

So my sad story is that my first prenatal appointment wasn’t till I was 11 weeks due to my health insurance. I hadn’t had a spot of blood and had full blown morning sickness for weeks! When they did the u/s, we saw that the baby’s heart stopped at 6 weeks 💔 and my sac was a 9 week sac. Ironically that same day I started to spot and have only had light bleeding since with no cramps... dr said it should happen in a week, it’s been 6 days. Has anyone stayed pregnant this long after? Is it ok to still let it happen naturally?