Very fun game! I like the retro style and and the music. One thing I realized while playing was that when you picked up the power up to shoot bullets quicker that if you didn't instantly used it, it disappeared. Other than that I did enjoy it a lot :D
I don't know if you've heard of Game Development World Championship before (gdwc2019) but it's a competition for indie game developers where they can submit their games and it's free! It's great if you want some more visibility for the game and it only takes a couple of minutes to join :)