It sounds like she doesn't feel safe. First I'd make a temperature gradient, so the snake has a warm and a cold spot ( by lamps or warmth cable ). You can also create a 'safer' place, add some branches, a plastic plant, ...

If she does not want to get handled, leave her alone for at least a week. She might just be in a bad mood.

Beware, I've never had corn snake's, it's just my experience of dealing with snakes