I saw your comments on Vimlark stream and I was really surprises that this was your first game! Really amazing work!
Some feedback:
- Controls and movement are really nice and responsive
- Great SFXs :)
- Maybe make the projectiles slower so you can see them and try to avoid them, this will add strategy to the game.
- I think that adding a roll mechanic could improve the game too :)
- You can use something call raycasting to know if the enemies can see the player before, will avoid the issue of them trying to shoot from another rooms.