most petco snakes are captive hatched. what you need is a small shoebox tub setup. your pretty much going to have to clutter up the tub so the snake thinks there isnt alot of room in there use waded up newspaper.
get the temps and humidity right(if they are not right that snake will not eat).
leave the snake alone as much as possible for one week tehn attempt to feed a live hopper mouse or a larger fuzzy mouse.