amazing game!
i really like the artstyle and gameplay
i wasn't a huge fan of the autoscroller camera, especially the seemingly random left turn in the last level - it made me lose track of my player a lot of times - maybe you could add a little icon that points to the player if you're offscreen
also having infinite bullets and time slowdown felt a little op - i have a couple of suggestions in terms of this:
1. make slowdown limited (or have it charge up so you still have to spend some time outside of it)
2. make slowdown faster
3. make bullets limited so the player can't just spam them
4. (imo the best way) add scoring based on how many bullets used and seconds of time taken total, with bullet time NOT slowing the timer down or the amount of slowdown used (or both), which adds a lot more replayability to the game and incentivizes you to not spam bullets and slowdown