I really enjoyed the artstyle for the game, I especially liked the background in the opening scene with the guy staring at your mouse position lol. I was honestly a bit confused at first, there was a lot on the screen and I had to read the tutorial text you placed while having to fight off other enemies; eventually I figured out the game loop though. Here's some other feedback:
1. You ignore all enemies by just going straight up. Since there is no enemy that can catch up to the player (especially in higher player speeds), it was possible for me to follow one direction and not take any damage. What I'd recommend is either placing boudaries or punishing the player somehow from going too far from the center.
2. Another thing to do with enemies and their speed, when you play for a while, enemies will get in a big group that is easy to loop; essentially, I just circled around the mob until I could kill them all.
3. Lastly, I kinda wished I could manually shoot the projectiles; I feel as if that change would make the player feel a little bit more in control of the player and overall improve game feel.
Overall, really good game, especially for your first GWJ, congrats!