All I have to say, is why on earth does unity want to have the same function do everything right on one script, and absolutely break down the other.
As for you, I mean, you don't have to finish your game this Devtober, the aim isn't to necessarrily finish a game, but rather a small demo, but most importantly learn good practices and take care of yourself on the way, so don't stress yourself, eat, sleep, stay hydrated, take a walk,... ;) There's always the next and the one after that and after that. Still sounds like an interesting idea! Which game enigne are you using? Will it be 3d or 2d?