This is why I don't like to comment on others ppl work too much. Artists are touchy (including myself), and when you ponder their work they tend to get a bit angry, even when you are right. So, maybe the best is that, if you gonna comment someones work, don't be a bitch. There is a nice way to say where are the mistakes and there is an arrogant way.
You can afford to be arrogant-art-mother-fucker but only if you are in the grand-master league, meaning: I would listen every word and advice if Pikasso would rise from the dead and comment my work, but if its some artist-wannabe then I would take it with reserve.
And that is what I see on art thread these days. Everybody are critics, and they can't even hold pencil in they hand. So, when you take those comments, good or bad, from those kind of ppl, do simple thing: let their words enter in one ear and pass through another. If by any chance something stays in your brain while it travels from one ear to another, then they maybe be right. Not because they know much more about art then you, but because you were blinded by your own arrogance while drawing it to notice you have made some mistakes.
Nothing is perfect. We are all human begins that make some mistakes.
If you draw something trying to pass some message from you to others through art, then there is a possibility that you won't succeed to translate your feelings through that art and show it to others the way you see it.
The main thing is that you feel good while working on it. And always remember: while you were working on your art you were getting better, going somewhere with it, while all those critics that do nothing but talk are standing still.