This isn't bad at all for a beginning game! The graphics are definitely the star of the show here, and I especially like the animations of the protagonist and the boss at the end. A few sound effects would have helped to make the experience more complete, but it's no big deal.
Thanks a lot for taking the time to play my little game ! Yeah the graphics are the thing I had the most fun with because i was already familiar with pixel art, happy to hear you enjoyed them ! Sound is something I still struggle to add into my games but you are right that it would have made the game feel more polished.