As far as regurges go, definitely read the full FAQ's about them. Kathy's advice is very helpful. As sort of a quick (and not exhaustive) review:
-Wait 8-10 days before feeding again
-Feed smaller items for the next several meals (not just the first). After a regurge, I go down all the way to pinky heads for the first meal or two.
-If possible, give Nutribac a try to get the "good guys" back in your snake's digestive system. You can lightly dust the prey item, but you might also try mixing a little of the powder in his water so that he can be getting some of it into his system before he eats. I would switch the water out at least every other day.
-Try to limit all stress from handling or other means, and keep the temps warm enough to aid in digestion.
Good luck with him