Why is minecraft controlling itself?

Try turning off the console or PC and see if they does anything. Or maybe your controller has a bug

If its just moving the one direction and walks into blocks and doesn't jump over them, just walks into them, then its a minecraft glitch, you just have to press the key again so if its going forward just press "W" or whatever you have set your controls to forward.

It's probably due to your keyboard keys getting stuck down. Even if they don't look like it, they can get stuck and at angle and cause you to move and go places without you even doing anything. It happens to me all the time. Next time it starts doing that just press ESC and go to the menu, then try unsticking all the keys you use. That is if you use PC or Mac! If it's for Xbox or psp it might be the same problem with the buttons. If it's on PE then it might just be that it's glitching. Hope I helped!