very nice game! but when making pixel art try to keep every pixel the same size so it wont look funky, and make the enemies shoot because they looked like peaceful creatures, and try experimenting with UI because it will make it look better and give more feedback to the player, oh and try to make multiple sound assets of the same thing but with a little difference for example make 3 shooting sound effects which are quit similar but has a bit of difference so it wont feel repetitive on the player, limit the shooting rate of the player because you can just spam click to destroy enemies. but for a first game and first game jam you did a really good job! (this is my first game and game jam too to be honest), oh and my last note is to use the particle system! it adds a lot! good luck !