Well done for making it to the end of your first jam. This is the first one where scope was an issue for me. If I had more time, I could have added more in but the point of a game jam in my opinion is to operate under constraints and learn how much we can fit into the time while having the opportunity to try different things.
Testing is always important, during development it can help identify areas to fix or polish, afterwards it ensures that what was made works as intended.