From what I've understand, the blue projectiles are the main source of damage and the red projectiles acts like a stun, making it so the enemies can't change lines. I think the concept is great, but I think you should explain in what the projectiles are different to make it more clear; if not in your game, maybe in the description of the itch.io page.
I also found it somewhat hard to land projectiles on the enemies, as you need to shoot 2 to 3 lanes up/down from where they are, in order to predict their movement (or maybe it's just that I'm bad lol). I would maybe add a score where you can see how long you survived to make the game more engaging. Other than that, great game !