In my opinion: to summarize, pixel art is a hand made drawing style that consist in placing pixels "one by one". Imagine that pixel art is what you can do in MS Paint only using the pencil tool.

Let's not bite the poor kid's head off.  He just needs to be informed.

grnbayfan, please click on all these links they've provided.  You will find out what pixel art is if you do. 

 Not to sound like an asshole, but... So you just stumble across this website called "PixelJoint", which contains tons of art not at all like yours and almost having a classic videogame-ish feel to it, plus the fact that the rules flat out tell you to post PIXEL ART, and think, "Hey! I should post my works here without informing myself!"

Also, here's a better guide to what pixel art is, in my opinion:

http://www.pixeljoint.com/forum/forum_posts.asp?TID=11299

Well, at a basic level a pixel art piece is a piece where every single pixel in the piece was drawn by your hand. I higly doubt that you hand bicked those gradient colors.

  http://en.wikipedia.org/wiki/Pixel_art I advise to study this article ...

 What exactly is pixel art?

 I don't quite think you understand the meaning of the term "pixel art".

This doesn't looks like pixel-art and this seems to have alpha color.

Not quite pixel-art. You used way too many colours.