Why does Ctrl+P cause strafe walking on start, while clicking Play doesn't?

I'm having this bizarre issue where using the Hotkey Ctrl+P to enter play mode causes the FPSController to strafe walk forward and to the left. I can still control it, but as soon as I stop it pulls forward and left again. This behavior is avoided by clicking the play button directly, but I can't figure out what's causing the hotkey specifically to auto-run in a weird direction. Anyone have a clue?