when running on a wall, a ledge or upside-down it can change your orientation making you run backwards, you have to stop running to reset your direction.
That also happens with acrobatics. It's not a bug per se, it's how the mechanic works. When you press forward, your character moves away from the camera, and it won't change directions unless you interrupt the movement. That's intended, you just have to get used to it. By the way, I think all movement styles could use an overhaul.
