The eye is misshapen. It doesn't look like a "ball" in a socket, as much as an almond shape with an iris. There is no tear duct, nor upper and lower eyelids, rather just an opening with lashes applied. You also have no depth to the eye or the socket. It's all quite flat and looks somewhat like a cartoon eye, although the coloring of the iris is quite intense.

Here are some very good articles you may want to check out to help you achieve a more realistic effect:
http://drawsketch.about.com/od/drawingportraits/ss/draweyes_3.htm
http://www.artyfactory.com/portraits/drawing_techniques/drawing_the_eye.htm
http://www.ehow.com/how_2109633_draw-eye-conte-crayon.html

thanks

i love the colors ,gl author