Let a friend borrow a charger,now it wont work for my netbook. Help?

I let a friend borrow my gateway netbook charger and now it won’t charge my laptop. There is no physical damage to the charger itself. I plugged it into my laptop and it instantly drained the battery and now it won’t charge the laptop. Could she have done something that made my charger fry my laptop? I can’t even get any other charger to work in my laptop!