Great job! I really like your visuals and sound design, you have a solid base for a very fun game. The sounds are REALLY good.
You have all the systems you need to flesh out the game if you wanted to, like building a boss for the end of the level that floats back and forth and much more slowly approaches the player- all while still having to dodge the other things as well (plus projectiles perhaps?). Powerups, enemy fire- there's so many different directions you could go, if you wanted.
Grats on your first game jam submission! I hope to see you in more!