Hey, neat little game, congrats on making a functioning random dungeon generator! Like others have said, the enemies are a bit repetitive and aren't particularly interesting (perhaps they could shoot projectiles or move in some interesting way?) Shame that I couldn't seem the boss or ending...
As for other feedback, I'd say that the fire rate was a bit slow, especially since each enemy took two hits to kill. Also, the way the camera lagged behind the player made it hard to see what was ahead of you. The rooms could have been a bit more interesting, perhaps there could be some traps or hazards, or maybe different rooms could be different shapes? If there was to be more variation, you could make bigger, more interesting dungeons that could be fun for even longer!
So good job with your game, I particularly liked the animations of the player and the different particles used for hitting enemies. I'd say that with a bit more variety, this could be a really cool dungeon crawler!
EDIT:
Was just thinking about my final remark of 'this could be a really great dungeon crawler', and I just want to add that if you do develop this further, see if you can find ways to innovate. The dungeon crawler genre / roguelite has been done a lot, so perhaps try finding interesting mechanics to differentiate yourself from others, whether that be an interesting way to attack enemies, interesting bosses, traps or anything else that can freshen the genre. imo, the best way to engage players is with fresh and interesting gameplay, so please keep experimenting!