I didn't actually realize that there was music because the music and sfx slider started at 0%, I think maybe you should change that to like 50%?
The games art is very simple, and that's ok. With the effects and everything I think the game looks quite nice.
The gameplay however isn't very readable. From what I notice the spinning squares spawn, and then turn into a unique projectile, right? From what I've noticed, it's impossible to actually tell what project it will be, so I think it would be nice if there was some sort of indicator for where the projectile will be. Maybe there is and I haven't noticed.
I also think the 1 HP thing is particularly harsh, but I think the game is supposed to be pretty difficult. Maybe a mode where you have more HP but you go to a different leaderboard would be nice?
Overall, pretty good stuff, but I'd try to add more readability to the gameplay with indicators.