Given the situation, I would get the shed off before feeding. In the future though when sheds are going a bit smoother for you, pick a feeding day and stick with it. Like McKinsey said, they either accept the prey or not. Nothing bad will come of the snake skipping a meal. My snakes eat on Wednesdays, regardless of shedding, and they have no problems.

Connie's terry cloth trick works well. You could also try putting the snake in a wet pillowcase for 15 minutes or so.