Just hold left or right to move, you no longer need to mash or wait for your keyboard to repeat.
I found this game off YT, and for a first game it's pretty good! One thing that bugged me was the movement though, it was like typing... easy enough fix for a normal scratch mistake. (See inside, comments explain!) If you have YT, I'd suggest subscribing to swordswords cause her videos are as good as her games. :)