Good way to implement the limitation! The mechanic it's interesting, fun to play. It took me a few seconds to realize that you need to rotate to take more than one ball, because they go always at your back (but that's on me, the instructions were pretty clear ^^). As others have suggested, a version with enemies or some other obstacle would be a neat addition. To propose something, maybe the timer maximum could be decreased as you carry more balls.
All in all, good job!
PD: I recommend you to upload de html5 version, this way your game will playable from the browser. With godot it is as simple as select the html export, call the primary file "index.html" (as itch.io requires), and upload a .zip with all the files that are generated. Then it suffices to check a box in the Edit Game page of Godot ("this file will be playable from the browser" or something like that).