Okay Stop. Now apart from just using reference pics get yourself a mirror and have a good long look at your face. The best reference you can possible have I would say.
Just look at the cheeks for starters, they are way too far across, the mouth is too wide the forehead is too deformed etc.
Now I could go on about whats wrong with your model, but I wont, I feel you need to understand the form of the head and proportions and how everything sits. Here is a link to a great site called fineart.sk. The page I have given has hundreds of images to download for free on how to draw the human head, they are all worth downloading printing and reading, to give you an understanding of the head as a form in itself.
I am aware of what you are trying to achieve and its not an easy task, Ive been there and am still trying to improve my skills as well as giving others crit. I think as far as your mesh goes is pretty clean and you have enough polys in most of the right places to carry on with this model. Also concentrate on one thing at a time instead of getting the eyes, mouth, ear done al at once. Get the proportions right first then move on to the eyes or mouth, get that done and get some crit then keep going until the next bit.
Heres the link http://www.fineart.sk/index.php?cat=14
Best of luck and be patient with it.