Hey, I'm from reddit and I have some advice for you.
First of all, keep the pixel art resolutions consistent, and make the GUI a bit more fitting to the style. Different pixel resolutions is one of the biggest problem of starting game developers.
Secondly, try removing the console and adding those text to the game as GUI.
Third, try making the "Subscribe to Pewdiepie" less obvious as it would make a great easter egg. It's cool
Fourth, try to limit the fire because it can be fired too fast and be misused.
Fifth, try adding a pause button.
Sixth,
Lastly, try to add music. Any 8-bit music (not overused) will suffice.
That's all.
I really love the concept, and the animation and gameplay is really satisfying. I wish you could simply press a button to retry. And I wish for some checkpoints too. I'm looking forward to this game.