I like the Soundtrack and the Background Scenes are nicely made as well. For small improvements i find the movement a bit wonky but that could also be me. It is a little bit weird how he jumps and feels not very controllable and the graphics could be pimped a little bit as well I would try do create all Art as PixelArt you can do that via this Website if you don't have Photoshop https://www.pixilart.com/draw. And if you get stuck you can't easily restart the Level.