Exactly. If you are not done yet, it is best to take a break. Put your drawing somewhere you can't see it. Get a drink, go for a walk, watch some TV. What happens is your mind narrows on trying to get the drawing perfect, you don't see the mistakes anymore. If one part is off, the rest of it follows.
The more I shaded and smudged and erased, the more things seemed out of place and Maki began to look like someone or something else. We don't want that.
I'm about an hour into this drawing so a 20 minute break does me good. I decide to redo the whole mouth. Next...