As joaokrejci said, I see some potential here. At first, I honestly thought the entry was not really good as the combat was not interesting neither the simple platforming. However, the jet pack was a nice surprise and it spiced up the platforming, together with the mushrooms. They both opened the world and it was definitely the best moment of the game. The little melon is cute and I liked the rolling jumping animation, for whatever reason I found it super nice to see!.
My main input here would be to reconsider the pacing of the levels and its challenges. It felt that the levels were too big and the challenges were not really changing. I think less enemies and more interesting situations would make wonders for this game, kind of like concentrate what you have in less space. Apart from that, I found the combat not really well executed as when you hit an enemy, it will immediately hit you back since there is no knock back to stop their movement, so it makes you feel that you did it wrong. I found actually more fun (and more efficient) to just skip enemies by jumping.
Overall, a nice entry :) Congratulations!