Better animation comes with time and practice. For your first flash it is not too bad. I kinda feel like you were excited to upload this when you could have made it longer. The horse actually didn't look too bad. Though there were parts where the under lying frame of the horses body and the layer with his legs don't sync fully. There are gaps and u can see parts of the background. Sound effects would not hurt this either. BUT it was not bad, i liked the song i am curious of where this is going. Good first film buddy!