I am really glad he is alive, now you need to get a little "schooling" so this never happens again.
On every topic on this site are "stickies" at the top of each page; they are extremely helpful hints and knowledge from the moderators or breeders who are on or run this site. Read them all.
YOU MUST HAVE A SOURCE OF HEAT FOR YOUR CORN!!! They are cold blooded creatures and need to have a place to be warm. This is not optional. In some books on the topic of heating your tank (which is a must since you don't live in the tropics!), they might mention heat lamps. This is a debated subject here, but I would not waste time or money on a heat lamp, go with a UTH (under tank heater). This will cover 1/3 of the bottom of your tank, and you MUST have a thermostat to regulate it, otherwise the UTH can reach temps that can harm your snake. Along with the UTH and thermostat you need a probe thermometer or infrared thermometer.
Corns use belly heat to help digestion, so a UTH with a thermostat is recommended over the lamp. It also costs less in the long run and is easier to maintain temps. It will help keep your humidity levels up too, since the lights tend to dry the viv out. Lamps can also harm your corn's eyes if the wrong kind of bulb is used. You want to set the thermostat to about 87° so the top of the substrate on the warm side is 85° and the cool side (where you would keep the waterbowl) is around 75°.
Have you done any book reading about corns? If you haven't, take the time to get at least a couple of books on corns. Two of the best were written by members of this forum, and will get you in the know on everything corns.
Kathy Love's book
Don Soderberg's book
Nanci has a great caresheet on corns, it will tell you a whole lot in a little time.
Nanci's caresheet
Here is a good guide for feeding corns, when to move up in size of prey. Most of us here use it, some think it is a little aggressive for younger corns so there is room to wait until your baby gains even 5g more than the chart says. It is known as the Munson Plan.
Munson Plan
I suggest getting a digital scale if you don't already have one, you need to weigh your corn and the prey. Almost all corn info is taken in grams, this is one I recommend.
digital scale (in grams)
I keep a journal on all my corns, I weigh each before feeding, look them over for any injuries or anything out of the ordinary, then feed. I record the date, the weight, what they ate (or didn't), when they are blue, when they shed and any other things to note.
I really am glad he is okay, and I hope you don't take this as a verbal lashing but as a learning experience. Everyone here is here because we love our corns and only want the best for them all. Good luck to you, and make sure he gets cozy soon!