Give him 2-2.5 weeks to rest and rebuild his gut flora. When you feed him again, go for a very small meal and only one prey item. I would also get a fecal sample to the vet so you can possible find out the cause for the regurgitation. Snakes don't just regurgitate unless something was wrong.

What did he eat last? Was it too big, an improperly thawed rodent? Do you feed him in his enclosure or a separate container?