My XBox 360 Controller isn't working right

Everything on it is fine, except for the left joystick (X Axis according to SRB2). Whenever I turn it left and right (even in other games), it doesn't read it right. Should I recollaberate (sorry if I spelled that wrong) the controller? There was some sort of warranty, but I forget for how long.

Is this only in SRB2, or across your entire system?

I had the same problem with my wired one. The Left stick would always move the menu/character to the right a lot. But, you can switch your left and right stick controls up slightly. For moving forward and backward could be pushing up or down on the left stick alone. The right stick could allow turning (move the stick side-to-side) and looking up/down (move the stick up/down). My 360 controls actually feel like a FPS control layout.

It happens in MUGEN, Super Mario 64, not just SRB2.