well, it this is a, it not you its me situation, lol I am not used to key board controls, I know right I am making indie games and I use a controller and not a key board and mouse .
I am trying to get accustomed to using mouse and key board, I can see that a lot of time was spent on creating smooth character control for your game. I mapped the controls to a controller and played it again and it was easier for me.
one other thing that I noticed when playing is is that in my opinion the camera should be a little wider or more offset so that the boss is easier to see while I was playing it seemed to be hidden under the health bar UI.