Nice game! I really like the UI, I think it explains what the game is about very well :)! Another thing I enjoyed is jumping on the enemies :D.
I think the player shooting is something that could be explored better, since it's discouraged to take shots in most of the levels. Sometimes there were a bit too many enemies for my taste, but the level resets very fast, so it's easy to jump right back in :).
Well done, especially considering this is your first game (at least on Itch.io)!