Great start! Your art assets have a lot of character, and I like the colors. Concept and world seems fun and interesting. Control and movement definitely need some work. Moving around is disorienting. The controls don't feel reliable, I often don't jump when I hit the button, or move in a way that I did not intend. I suspect the player is moving much too fast, but this depends on the gameplay to a degree. Consider a 16:9 aspect ratio. When you jump, you go rocketing up into the air. Little trick to prevent this while keeping things from getting too floaty: lower the global gravity and the jump velocity, then increase the players specific gravity while they are falling. The early Mario games did this.
I think you have a knack for interesting concepts; the player character, the gun, and the cat wizard are all good. With more polish to the movement, to the point where is it a joy to simply run and jump around, I think you'll really have something here. Keep it up!