This is quite good for beginner level, especially considering you made it in such short time.
The gameplay is relatively decent. The art style and music are nice and pleasant to the eye. Adding a variety of weapons is a good idea- it helps the gameplay feel less repetitive. NPC movement speed felt nice - not too fast or too slow.
The feedback system is pretty effective- you assigned different colours to the particles depending on whether the NPC is hit or killed, and a clear feedback for when the player takes damage - both particles and character sprite blinking. Great job with this part of the game.
Few suggestions that come to mind are-
1. you may want to reduce the screen-shake a bit, or at least change the intensity according to the gun in use- pistol: low shake, RPG: high shake, etc.
2. Depending on the weapon that the player is using, you can spawn the number of enemies to match with it. Some people like using guns with high fire rate, so when that gun is equipped, spawn more enemies; when pistol is equipped, spawn fewer enemies. The idea is that the players should feel like they are getting the most out of the gun that they want to play with.
The game is quite good and has potential for improvements. Overall, nice work!
Viewing post in WAVE after WAVE jam comments
Thank you for the feedback! Reducing screen-shake on lighter weapons and then crank it up once you get to more heavy artillery is a really good idea and I'll try to add it as soon as possible.
Giving the enemies guns would probably improve the gameplay too, since instead of just mindlessly running around and maybe sometime avoid danger, you'd actually have to dodge enemy attacks.
Both great ideas, thank you for the reply!