Very impressive how much content you've got, and how complete the game feels (3d, menus, cutscene animations, collectables, audio, etc.)!
Like others have commented, I found the controls quite difficult. To the point where I kept missing the jump in level 2 (I think the next cloud was either above me or to the side, but I couldn't find a reliable way to line it up).
I hope you continue this one because it's a great start on a full game, and like I said impressive for only a gamejam. :)