cornsnake eating

Question
We have a young corn snake who ate well for 4 feedings.  We feed him a pinky once a week and he has always eaten quickly, even with light and an audience.  One night, I accidentally turned off the heating pad.  I also had difficulty keeping the temp. up to 85 on the warm end.  I have corrected this problem with a warm end temp. of 85 and a cool end between 70-75.  He usually resides in the middle or on the warm end. He still drinks well and is active and alert when handled.  He has not eaten for 3 weeks.  He looks healthy.  We have tried wiggling the food, fed him at night in the dark, we don't touch the pinkie, we have water and room-temperature warmed the pinkies.  Any advice?

Answer
My advice would be no handling until he starts eating regularly again. Hatchlings can often have problems feeding.If you are using a heat mat, how are you measuring the temperature and where abouts in the tank are you taking a reading? If it was my snake I would try feeding him in a small tub with some air holes, put it in a dark place and leave him there for a few hours to see if he eats. When did he last shed and how old is he?