I missed giving Critiques...So I'm back
First off...What the hell is going on. It lacks the detail to really define any means of shape. Anything would help; Well placed shadows, highlights, just details in general. The jagged edges on it too really do not help your case. I'm torn between deciding whether or not you drew it in another document and copy-pasted or was done with the pixel tool, it just looks awful. If it messed up while saving, amp up the quality or use a different file type.
Guides are your friend, and you probably could use some. On a separate layer draw perspective lines, It will help you not have a piece where the whole body looks contorted as all hell. Being as blunt as possible, in the nicest way, I dislike the background, especially the dirt/grunge thing to the left. It doesn't fit to me, maybe because I can't tell what's going on. But get rid of that. Overall just as a recap, watch the quailty, use guides, and watch what you use as a backdrop.
