Honestly for being a solo submission and starting late I think this is a great submission. your going to hear it a thousand times but game jams are the best way to be motivated and focused on making something I definitely wish I started doing them sooner. And jumping into this with little experience is awesome and what you made while learning is a great foot forward. As a personal opinion unless you want to do something else I think you should stick with this project. When completed it will help you learn alot about game logic/code, making shooting projectiles, health system, enemy movement system and how to detect damage. Then when your done and move on to a new idea or project you wont need to look up video you can go back to your old work like this one and have something like an enemy spawner already made and simple to add into the new project. Great work :)