Curious Aratol, are you using layers palette and then merging them when finished. Where are you at with experience using Photoshop? Its one of the areas I teach in art at my school.
One criticism is the size of the iris. Taken from DaVinci's studies on cadavers and used in a unique system I put together to construct portraits...the height of the eye is one iris diameter in height. The length of the eye (that is corner to tear duct) is equal to twice the height of the eye...or 2 iris diameters. The distance typically between one eye and the other is one eye length apart. Width of the nose at the nostrils on caucasians typically is the distance between the eyes.
Such being the case, and without seeing your reference...I would suspect that the distance between your eyes is too great, and your irises too small in diameter.
Also, if you draw a line straight down from both pupil centers with the mouth at a relaxed state, they would line up with the corners of the mouth. Meaning your eyes are too far apart again, and perhaps the length of the mouth too small.
Now that brings me back to asking if you worked in layers...because it is a small matter to go back prior to merging, (if you haven't yet), make the small changes I speak of with relative ease.
Hope that helps.
"Painting is easy when you don't know how, but very difficult when you do!" Edgar Degas
[This message has been edited by lseiler (edited March 10, 2001).]