Yeah, if the minimum value on the counter is 0, it won't be able to go into negative numbers.
But you still haven't addressed WHAT the problem is; are projectiles being destroyed when they hit walls/enemies, or is THAT not even happening. If the projectiles aren't even detecting walls, its most likely a problem with the looped movement; too big of a pixel offset from the direction calculator.
i rewrote the code and its working now for some strange reason
the problem was nothing happend and i couldnt exaltcly see what because fastloops makes it too quick for my eyes ;p