The main character is very floaty with movement, all you really need to do is add a very strong de-acceleration and then it won't be floaty. Graphics are really good, needs shooting sound effects. and maybe an animation on the main sprite. The rest of it is very good. The escape key crashes the game and there is no way to continue. The UI text doesn't scale well at lower sizes when not running in full screen. It's a really good start and I hope you can make more with this.