WEll, i gues its not bad, but im not even 13 yet (3 more weeks)! So don't be using age as that. Its ok, if its your first model in 3d. But, of course, there are many places where you can improve. I suggest going over to www.learning-maya.com
and do a bunch of their tutorials. But, keep on working, and you'll be better, like the other people said.
A tip for rendering:
I see that you are rendering using mental ray. But if you want something that will make it look clay like, like a lot uf us do, heres how you do it!
Go into mental ray options in the render globals thing. Then turn on final gather. Change the amount of FG rays from 100 to 500, or if you have a kickass machine, 1000, or maybe 1500. Then put the object on a plane, as you have done. Then make another plane as background for it. YOu don't want to be seeing that annoying black color as your background. All of this can be, and should be as Lambert 1. Now you make a plane for the light, and assign it a new lambert color. Turn up the incandescence, and increase its size a bit. Also, in the common render globals section, turn off enable default lights. You can change the color of your incandescence, so thatyou get a different color tint to the lambert. Pure white incandescence makes lambert 1 turn grey. I like to go with a nice steel blue incandescence, but sometimes a more orangish-yellow. If its too dark or too bright, ton't mess with the incandescence of the plane, instead scale it to be larger or smaller, and this will adjust how much light it is giving off.
That's how you do it then! Keep on working, as I said, and as everyone else said, and you will be very good eventually like metallicjet66, and hes only 14! :p