Awesome reaction to negative feedback, dude seems like a total Jack TBH, don't even worry about him. Even if his criticisms are legit, he wasn't polite or very helpful at all. This is a pretty awesome effort for a first Jam, going for a platformer style game is a classic first attempt.
Biggest issue I had was the game froze up when I started level 2. Other than that I think you'll get the hang of controls and art direction as you continue your game-dev journey. A Subjective suggestion to improve user experience other than refining controls would be to zoom the camera out a little more so its easier to navigate the environment.