Cursor speed too slow?

I don't know why this happened but my cursor speed has dropped. Significantly. I used to be able to move my mouse around a lot faster to perform specific mechanics, but I no longer can. My mouse doesn't move fast enough. I can't even play properly because of how slow my mouse is moving. Is there any underline issue that could be causing this? I have my cursor speed on max and max in game and it still can't keep up. It used to be faster, now its slowed down. I don't think i'll be able to play league ever again if I can't find a solution to this. Help would be very much appreciated.