I would be reluctant to do any corrections to a pastel after having been told by the customer that she likes it! Pastel is very easy to overwork and demolish!
However, I refer to the line which passes through the eyes as an axis. If you carefully look at the eye axis in the reference and in the drawing, you will see that the reference is more nearly horizontal than the drawing. Then, you will see how that has affected the whole facial drawing. But, I would not touch it at this point if I were you! Corrections are harder than drawing it right the first time.
