Nice game! But I do think it needs a lot of polishing and bug fixes.
If you do plan update this again, focus on adding sound effects and music. If done correctly, it can hold your player's attention throughout the game. If you want to make music on your own my recommendation is Beepbox which you can run on a browser.
Also another thing I noticed is that the attack mechanic and enemies needs some improvement. It is really hard to attack enemies without taking any damage and enemies can hit you while loading the level. So it just makes the player want to tank them and because of that defeating enemies won't feel satisfying.
There are lot more stuff but I think you should be able to figure it out. OBV don't take this seriously. It's already amazing that you built a game like this at 13 years old. But if you do some more polishing, this game could be even better!