Art looks good and the gameplay is nice, The pogo jump is bit difficult but get use to it after a few tries, also I think the dash should be trigger when the key is press not on release. I also notice that the character falls faster after dashing.
Not sure if this is intended but the third door just brings me back to the main menu.
The audio in the boss battle continues to play after losing.
would be nice to have coyote time.
And lastly after the tutorial level I think players should respawn in the door room.
Other than that I think you did a good job :D