Thats a lovely drawing you have made, I like it. Somehow the design makes me think a bit of Chii from Chobits
I really like the colouring of the pony. Especially the colouring of the hair looks interesting to me, a bit odd maybe but off course thats a matter of taste.
I think the background is really interesting as well, to be honest it wouldnt be my colour choice, I would probably have stayed with the fresh and bright colours which you also used for the pony, yet this do looks interesting. I wonder how you made the background, it isnt pencils, is it? Im also not sure about Photoshop, it looks to traditional to me to be digital