Good job! You really nailed the game-boy style! I also really liked the tone-on-tone color palette! I think it has a lot of potentials! It's a great foundation for a bigger game! For this reason, I would like to point out to you some small issues/bugs I noticed (maybe I already know about them):
- (don't know if it is intended) you can trigger multiple times the first dialog box ("what? ...etc...)
- some problems in spawning the first set of spikes here are some examples (there is also an invisible spike in there, visible spikes change when they enter the window):
- the first fish: if you got hit and then stand still, the fish cannot hit you again (as long as you stay still); you cannot kill the first fish
- the HP bar rendering layer relative to enemies and spikes (HP bar momentarily behind them)
- bullet facing direction
- performance/frames drop in the big room with the jellyfishes
- you get the weapon, go to the next room, then return to the previous room, you have to pick up it again
(sorry for my pedantry, but I think can be helpful) Anyways, nice game! Keep up the great work!