Why won't my in-app purchase load, yet I still get charged for it?

Let me start from the beginning- yesterday I got an ITunes giftcard, and I used some of it on a game called MinoMonsters, which allows you to get credits to get unobtainable things. So I bought the credits, but after a while it said "failed to connect to ITunes store" which is a complete lie, since I was charged for it. Yet none of my credits are showing, and whenever I try to spend them, it says I need to bit some. Really?! Then I thought that I should contact the game developer after the "restore" button in-game did nothing even though it said it did. But the only websites that you can contact him on are pay-to-register. I don't like being charged for something I know I paid for, please help!