If it is a hatchling that would mean that it is probably not more than a month or so old as this years baby. With that in mind, I really doubt that it is eating 2 pinkies at a time already. Your supplier may not be giving you a truthful history on this babe.
Corns are rarely finicky eaters. DO NOT feed it magots, crickets, or frogs. It probably wouldn't touch them anyway. The idea of letting it settle in and become comfortable with it's new home is a valid home and may be the whole explanation. Two weeks is not a great deal of time especially if it had been eating regularly before. So don't panic yet.
It sounds like you have already tried some of the tricks already but let me tell you what has always worked best for me. Find the smallest live pinky you can. Brand new out of Minnie if possible. Run it under some warm water and gently was it off and then towell it dry. Be careful to not hurt the mouse. Put the mouse in a paper lunch sack and put the snake with it. Fold over the top of the sack and staple it shut. Set it aside where it will be warm but not hot. Now leave it alone for 24 hours. Try to stay completly away from it, don't turn the room lights on and off, just leave it alone. This almost always works for me.
Other things to consider, is your heat correct in the cage? Does the snake have places to hide and feel safe? Is someone playing with the snake alot? Is there a lot of noise or traffic by the snakes cage? Does the snake have other snakes in the cage with him?
Hope this helps, Don't stress out but if you don't see progress in another week or so check out the guys on the cornsnake forum, some of them are pretty smart.
Wade
