Haven't had a single issue, it's all in the player control, every action is directly related to the direction, B+Up does an Up attack, B+Down does a down attack, B+Side does a side attack, B does a standing in place attack.
It can't get much simpler than that. You won't be doing wrong attacks unless you, the player, is failing at the input.
Also Y is not for regular special attacks, it's to grab the wall and, much later in the game to do wall-related attacks.
Also your example is false, if you're near a wall and you press B, the character headbuts, even if you're already grabbing the wall and you press B the character will let go off the wall and headbut (I took the time to go and check).
For what you describe to happen, you would have to be pressing Y and the opposite direction of the wall, and if you were doing so while trying to headbut (B+no direction), well, I don't see how it's the game fault that you were pressing a wrong button and an extra directional input.
There are some dubious choices with the a few gamepad buttons (mostly the chicken and dimensional shifting not really being positioned in the gamepad with any logical consideration), but it simply sounds that you suck at playing the game (probably due to lack of experience with a gamepad).
