My PS3 controller is borked?

Every time I try to use my PS3 (Doesn't matter which game), my controller starts doing these weird things all by itself. It randomly presses start, turns itself off, scrolls in different directions even though I'm not even touching the analog stick/d pad, etc. I'm not doing anything, I can just lay it down and it'll do things on its own as if I'm pressing the buttons. This isn't the first PS3 controller, I got it new at GameStop after my old one broke its R1 button. I've turned the controller off and back on, restarted the console, etc. But every time I try to play a game, the same thing happens again. How do I fix this?