I just reloaded a save and when I tried to walk, I couldn't. I can move the camera, I can jump, I can swing my sword, I can open menus, I just can't walk. I've tries fast traveling somewhere, tried restarting the game, tried loading a previous save, tried toggling clipping: nothing works.
Tried it. Tried two different keyboards and two different Xbox controllers. If I hold sprint and do a whirlwind sprint I can do this weird run where in doing the run animation but moving at walk speed, but only in third person. If I go to first person I go back to not moving.