Great job for your first animation, this right here is what a first time submission should be, you put a lot more effort into this than most people put in their practice animations, at least you bothered to finish it instead of making it only a 5 second loop with no sound, colours and all sketchy.
Nice touch having several parts of the movie sync up with the music.
Simple but kinda nice to see the adventure of this little red ball. Keep at it!