Pretty nice concept. I love the idea of bullets ricocheting and becoming part of the....well bullet hell.
The game plays well, and is fairly challenging. I also really like that you are not shooting enemies but instead shooting their projectiles, it makes for a cool subversion of the genre.
My only feedback is that the walls are a bit too unforgiving on the player, if you update after the jam, consider making the player hurtbox a little bit smaller so that the slightest graze does not kill you.
Had fun with your game, you should def update it and tweak it after the jam.