holy mother of god there's no nose

Eh, this isn't anything great. Anatomy is very far off and it doesn't really have much more to show for. The face is horrible and does not fit on the head, and the muscles are to put it simply, wrong. I don't think going indepth into all of this will help very much. I recommend practicing basic anatomy above all else, maybe learn a bit of shading to. Look at some tutorials, practice and develop your own style.
http://www.posemaniacs.com/
This is a great website that allows you to look at detailed 3d models of humans in a huge variety of different poses and angles.