Ahem
Your 15 I see... meaning u likely do not attend a high level school.
I've heard MANY school bands... none... and I mean none... have ever produced sound of this caliber... expecially from kids your age... it just doesn't happen unless u go to a school for the extremely gifted.
And not to mention wealthy... since I hear an assortment of instruments that would be extremely expensive for a school to own. Of course u say u added your instruments.... but I doubt u have anything so elaborate that you can synthesize any of what I'm hearing... and not to mention fit it in so well. I'm sure with a bit of searching I will find this exact piece played sound for sound, except credited to the proper author.
Be ashamed... be very ashamed... the people here aren't stupid.
excuse me while I blow he whistle and let the admins have a listen for themselves.