Can't do anything while ingame?

So for some reason, whenever I load ingame, instead of getting the League of Legends mouse hand onscreen, I get the normal Windows one, and I can't do anything ingame...I can hear and see everything, but I can't type, move, level up abilities...nothing. It's basically like I've tabbed out of the game and it is still playing in the background, but I haven't tabbed out. I noticed that, in the loading screen, the actual ingame mouse appears for a split second, then quickly changes back...any fixes for this I should know about? I've already tried exiting the game and reloading, completely restarting my game, task manager force-quitting, and nothing works...I really want to get this fixed so I can actually play, so if anyone has this same issue and has a fix I'd love to know how to fix it :D

Also im getting low priority queue because of this so plez someone help