Controls/abilities not responding a lot

After this most recent patch, I've had an issue with controlling my champ. Not all of the time, but a whole lot, my champ won't use abilities when I push Q/W/E/R, won't change direction/stop/go with mouse clicks, and with sometimes stay in one spot twitching back and forth in one place. It really destroys my ability to react or contribute to plays and fights. What can I do, hopefully not reinstall? I have barely any space on my main drive, so I get real problems with installing things.