Ok, here's my honest opinion, although I am not sure how much you'll like it.
To begin with, you should have included a score to the piece. Anyway, here's what I think, without the score:
I think the piece is pretty good for a game. And I am not talking about games like Morrowind or Knights of the Old Republic. It sounds more like the music games such as Zelda have, jumpy, happy, simple.
About simple: you use some pretty cliché chord progressions, and at points the piece gets very predictable, and maybe boring. The writing is very idiomatic for both instruments, and there is not much originality, I believe (not as much as you could give, for sure
). About the story of the fantasy, I can hear the distinction between the chord progressions and I can feel some changes in terms of texture, but that would sound more like a question/reply thing, or just a recurring instance than a "story". It would take a lot more to build up on a "story" (for example, check Brahms' Ballade "Edvard" and search for an analysis of the work).
Bottom line is, I wouldn't like to hear this piece in concert. 14 minutes is a long way, and to make 14 minutes sound interesting you have to try harder than that (I believe).
Sorry if I have offended you in any way with my comment, but this is my honest opinion. I think you should broaden your listening experiences, and listen to more modern stuff, even starting from Debussy and Ravel, and going further to people like Stravinsky, Schoenberg, Berg, Messiaen etc etc. You really need to get examples of people who did something original. Unless, of course, you wanted to write a piece which would sound like a gameboy game. If this is what you wanted from the beginning, then no problem, it's good stuff. But if you wanted to write good concert music, this is not the way to go, I believe.