Gamestop 360 controllers?

So i just bought a gamestop controller for my 360, i didnt have enough money for a regular controller. But everything works fine, execpt the X and B ons seem to be the same on. For example, im playing ninja gaiden 2, and X is quick attk and B is projectile, once i start to attk by pressing X, i get two hits in then i would fire a projectile for no reason. Same thing happens to SF4, i specifially put short Kick to B and yet i get small punch which is the X on. can i fix this?