It's totally fine and don't give up! This is my second game jam and I serve it as a chance to learn the Godot basics like how to use Tilemaps and Animated Sprites. After spending 2 days researching how to do the reflection and sliding effect, I had no time and could only submit a prototype without gameplay, and the lesson here is to plan for a super mini game when the jam period is so short. Nevertheless the experience was still rewarding, and game jam is also a good opportunity to play and learn from others' games~ =w=