I just played your game and want to share my personal opinion.
What I like—visuals and level design are implemented nicely. All of that is fitting the theme as well, so that's a good job.
What I didn't like - the level design in terms of player progression. What I mean by that is we should never make players spawn on top of the enemy—it does minus 30% to the game perception. The number of enemies at the very beginning of the platformer game is inappropriate. As it was mentioned, collisions are a bit bugged, but it is fine, I can deal with that.
It is a fine project if you are a beginner. So if you are, then good job!