Great job on finishing your first game jam! It's not easy to finish a game! How did you find Godot engine? I heard a lot of good things about it. I am curious to try, maybe in the next jam.
I disagree with the previous comment. This game gets a lot of tension in later levels. So many enemies are walking towards the player!
I think the game will get more interesting if there is more variations of enemy attacks. Perhaps you can introduce a different enemy with long distance attack in higher levels.