Ok, a few things to consider:
First, it's very important to determine WHY the snake regurgitated. It is either husbandry, stress or internal illness.
Was it husbandry related? Are your temps right? If your snake was too cold it couldn't digest properly and regurgitated.
Was it stress related? Did you handle the snake too soon after eating? Did something in the room spook the snake? Snakes will regurgitate their meals if they are scared. They will basically shed any excess weight to make escaping easier for them.
Lastly, if husbandry and stress aren't the issue it may be best to make a vet appointment.
Also, VERY IMPORTANT: you should wait AT LEAST 2 weeks to offer food again after a regurge as well as offer smaller prey for at least the first meal. Regurgitating takes a toll on the snake's insides. So basically you need to let the digestive system heal or you can make the issues worse.