Overall I enjoyed the game but I personally have a few things that i think could improve the game. First, increasing the spawn rate after death doesn't feel great and punishes the player for not being good at a game that they just started playing, especially if there not used to this genre of game. Second, making the UI bigger or adding some visual or audio signal for when a specific weapon is out of ammo could help since at first I thought my weapons weren't working but it was just because I had no ammo. Lastly, adding some sort of telegraph when the enemies are going to attack and adding a small cooldown could help since if to many spawn and crowd around you, you just die since you can't escape, you could also try implementing a dash with a cooldown to resolve this. Still, this is great job for your first game jam!
also, if you wouldn't mind and haven't already, you could rate my game Bomb Squad and give me some feedback.