A cool twist on the bullet hell genre. I was a bit confused at the start, but after re-reading the description, it was quite fun to play. If you want to continue with the game, here are a few suggestions to make the game even better:
The collisions were not really clearly visible and it was hard to tell when the player will get hit and when not. Making the outlines of the colliders more clearly visible and adding some FX on hits (particles, sounds, etc.) would help.
The arrow-key rotation of bullets seemed a bit too slow. Making it a little bit more responsive, possibly with some acceleration/deceleration to make it more smooth would enhance the player's experience and it could also make it look better.
Overall, really good job on making a game on your own in 48 hours, especially the music sounds great and fits the game well.