Well, I think you have very good pixelling technique and you've done great with only five colours. However, two things stand out to me.

1) The anatomy. I know that this hobbit / elf / whatever doesn't have normal human anatomy, but even so the arms seem very long compared to the legs. The upper arms seem a bit too long compared to the forearms (or forearms too short), and the stance is very weird indeed. It kind of looks like he's doing some lunges (google it). Finally, his leather (?) armour looks a bit too much like a naked chest, rather than armour, for my taste.

2) The shading is a bit uneven. The shadows on his neck and hair are quite strong, but his arms and legs are are almost pillowshaded. Some more dramatic (and consistent) shading would do wonders for this piece.

Hope this helps.