I'm sorry, but this is not very good at all. Even if you are a beginner, you should at least do some researching and learn about it before diving straight in.
The character lacks shading, depth, and any detail at all. it's hard to call it pixel art because it's not really pixel art, more like 5 minutes using the pencil tool in MS Paint. There is a ton of things you need to learn, there are some nice tutorials on beginning pixel art. Including
shook's.
You're going to need a palette to use, usually pixel artists aren't given every color known to man to work with, instead they use palettes, little swatches of a limited amount of colors. Otherwise, it's not really pixel art. You also need to learn shading, which is shown in shook's tutorial above.
If you have any questions, pm me or SlyBash. You can also contact me at my
deviantart page.