Nice, congrats on submitting your first game. I also created my first ever game for this jam. I couldn't get the WebGL to work properly either. I think the art is pretty nice and the soundtrack works well.
Some thoughts:
- The jump sound occurs after the jump. Should be an easy fix to have it play when the character jumps.
- I couldn't figure out how to attack. Once that's in the game, it should be more interesting to play.
- Maybe there's something you could do to make the item collecting more interesting? I'm sure this will come with time.
Overall, good job!