That was pretty neat. There was an interesting story going on there.
However, I feel like, because you wanted to keep everything to the beat of that song, the pace was too slow.
Pretty much the only thing that happened for the first minute was that they were just standing there doing nothing. I feel like a chase sequence or a struggle could have happened to fill out the time there.
But for your first animation, this is quite impressive. I do hope you continue animating. You have potential.