i have trouble w/purchasing on my itunes account, when i try to purchase i put in my password and it sends me to a different page. Then it gave me 2 questions that i must answer, which is Q's i dont know/ i didnt choose.What the **** do i do?

I'm currently having trouble purchasing on my itunes account w/ my new itouch 5. I get a message saying that they require additional information first, I enter my password to procede and it takes me to a page with two questions which i must answer correctly. (so here's the problem)I dont know the answers to these questions because its not the question i have choosen for my account. My security question is What is my mothers name?, and it doesnt show up!, it actually gives me random questions to answer that i didnt set to answer. And every time i try again by taping purchase on a app and i put my password in again, it gives me DIFFERENT answers that it gave me last time. It Doesnt make any sense!!! im very angry! Please help!