hes rubbing his crotch 
...
somehow 'no...' just doesn't convey my feelings towards this comment enough.
anyway, there are some inconsistancies with this piece. His arms seem to be different widths. his hands are mittens, the collar of his shirt looks unnatural, his waist seems too high, his feet are pretty big, his legs look much too beefy, and other than the hair, which is acceptable, the rest of the palette could use some work.
I'd say drop a layer over the drawing you have now (if your software does that sort of thing) and redline the basic shapes of his pose and structure, then refine refine refine. compare it to photos of people in poses like this, anatomically correct drawings, etc. and once you feel confident with it, start to recolor.
This crit is more geared toward the "Or any tips on what I could do to avoid making the same mistakes?" area.
