Corn snakes dont normally eat worms so this sounds rather unusual!
You should really give it only pinkies - frozen/thawed ones are best.
Remember snakes can go quite a while without eating so dont get too worried - when was the last time he/she ate? did it eat pinkies before?
How recently did you get your snake? If it was only a couple of days ago its probably just getting used to its surroundings - you should leave it alone for a week or so to get accustomed to its new home
Are the temps right in your snakes vivarium? They should be 75ish at the cold end and 85ish at the warm end. If the temperatures are out it could put your snake off of eating. Some corn snakes also go off their food if they are about to shed.... did the petshop tell you when it last shed? Are its eyes glazed over and skin looking dull?
A method a lot of people use to get their snake interested in its food is to hold the pinky in tongs and wiggle it around infront of the snake so its thinks the mouse is alive
You could try slitting or braining the pinkys, which is cutting a slit down the back, or in the head so there is a stronger scent which the snake will be attracted too.... if it feeds this way, try it again on normal pinkys after a few weeks.
If this doesnt work you will probably have to try offering it other types of food, but ill leave it to someone more experienced to help you with that if needed.