HELP!! HOW DO I UNDO A PAYMENT FOR A VERIZON ANDROID GAME?

i accidentally bought a game on my android phone (samsung fascinate on verizon) which i did not wish to purchase. i used up all the trials and it said something like "click to continue" which, in android game talk, meant purchasing the game. there wasn't even any confirmation asking if i was sure i wanted to buy it. so... now im wondering if i can undo this transaction somehow or if i'm just going to have to call verizon myself