Regurgitation is usually stress, husbandry, or illness related. Once you're completely sure you've eliminated improper husbandry from the equation, you can go on trying to identify the cause.

I wouldn't handle at all for at least a couple of weeks. At that time, you can feed again and then not handle for at least another week (to ensure regurgitation is not a repeat occurrence). If there is another regurgitation, then you've likely removed husbandry and stress (at least from handling) from the equation and it's time to see a qualified snake vet.