Game ruining Bug [Gameplay]

When I played today, the first thing I noticed when I went ingame was that my cursor didn't change to the one u usually have in league, at first I thought everything was normal but that, but later on when I right clicked twice it pulled me out of the game, then when I tried to use an ability I had to left click and spam for it to work, a lot of other things are happening like this that make the game too hard to play, ive tried uninstalling and reinstalling, plz help! I don't know how this started or anything.