Not bad for a first animation.
I haven't done any myself, but if I were you I would put more time into the design of locations, characters, and the animation itself. Also, you could add sound, obviously.
Very important thing: do not use animations taken from games or such (Ex.: teleporting sequence)
But, overall, since it's your first, it's pretty good. Keep doing these, and each time you make a new one, try adding a new "feature", like, well, in this case, a Play and Stop button would be nice. Programming's a b*tch, isn't it?
Always remember: practice makes perfect.
- Kagekiyo -