are you trying to get a likeness to the photo? I did an edit
I wasnt totally able to get the likeness either. I completely re drew the face from scratch so I couldnt possible explain everything I did but heres a few points.
On yours, the individual features look pretty good, but they dont really fit together right. It doesnt look like a cohesive face, it looks pasted together.
Remember to take note of the slant the face is at. You have it in most places, but not the nose, you need to move the right nostral down 1 pixel.
Pay attention to the proportions of the bottom of the chin to the base of the nose, compared to base of nose to center of eyes, and from there to top of forehead. These three areas are ussually about equal. On this model the forehead is just slightly shorter, maybe because of the hair. Also note the ratio of bottom of chin to bottom lip, and bottom lip to base of the nose. They are about equal in this photo.
Also, the distance from the nostral to the corner of the eye, youve made it slightly too much. Shortening this distance and making the chin longer will emphasis that she is tilting her head back slightly.
Also pay attention to the angles of the contour of the face. It may be useful to look at your reference and pixel at the same time, then take something straight like a pencil and match it to an angle you want to check, then shift the pencil over to your picture without slanting it and compare the angles.
Other than that, hopefully my edit is of some help.