Well.....
First off, the head is way too big for the shoulders and torso to properly support. Even if you were trying to pass this off as some sort of bust, it still wouldn't work because of the way you out lined it.
The Eye sockets are both aiming in different directions. One is aimed up, the other is aimed down. Now I see that you have some blood on him and it somewhat looks like he has been in a fight. but him being roughed up won't explain his deformities due to the fact for his eyes to be like that, most of his facial structure would need to be broken, but then you don't have proper coloring or swelling. So him being roughed up is not going to work as an excuse.
And then the chin is out of line, it needs to be back a little more
As for your coloring and lighting, they have their own problems. most places you only have the base color and a shadow. Some times that works, but your usually better all with going with 3 levels of light and dark. Actually on a second look, you didn't do any highlights. Sure that might be one on the pin on his hat, but I doubt it.
As for coloring, it goes much with the lighting, the colors are very flat, thus making the picture very flat.
His clothing looks, well just drawn over top of him as if he was a flat plain. He needs to be more 3 dimensional. His clothing needs to flow with his body. Clothing will also bunch up and wrinkel where there is a lot of cloth shoved in to a small area, like the bend and turn in his neck and collar.
The blood looks just dabbed on as a second thought, actually him being roughed up at all seems like you decided to do it last minute to try and "Spice it up" but it didn't, this soup doesn't even taste like you added even table salt to it.
And the jpeg artifacting, it;s just painful. I'm not sure why this is so compressed, but that could be because of the over saturated color.
Do more planning
Get to know your structure
Do under drawings and build up structure
Learn proportions
practice color an lighting
work with posing and dynamics
research blood splatter and body damages
look at facial expressions
Perhaps after you study all that, you\ll have better results in the future.