Heating under a heat lamp can actually start to cook the prey which is not good. Most use hot water.

When offering food do not remove the hide. Just dangle it outside the hide a few inches and let your snake come get it. If it doesn't come out just lay the prey on the cage bottom a couple inches from the door and leave it be. Check on it in 20-30 minutes, give it peace and quite. No lights, sound, or movements. Being young it may be shy and when you remove the hide suddenly it will become scared.

I thaw my feeders in hot water and then drain the water and let them sit in hot water for 5 more minutes to make sure they are plenty warm to offer.