As a test, it's somewhat functional.
As a game, it's unplayable.

Maybe try again next time.

I can tell that you're just starting learning to making games but:
Arrow keys need to be locked because they are still scrolling the screen
A mixture of graphic styles is never good
It's really buggy. There's platforms that you fall straight through
Why have a gun if I can't shoot it?

EDIT: Then how are you supposed to get across? I've tried to give you some useful feedback rather than just rating low and moving on. I hope you continue to learn and improve.