A question about having to draw and the options you have right after

I've been thinking about this and wondering about the course of action you take. Let's say you draw on somebody for a legitimate reason (advancing on you with a knife drawn, pushing/shoving you around and threatening you repeatedly, etc) and this stops them in their tracks. Now what? Do you tell them to leave? Do you tell them to get on the ground and you call the cops? Do you back off and try to escape? If you drawing stops them in their tracks, what's the best next step? Assuming they don't just run away. Thanks via /r/CCW http://ift.tt/2bDfFE6