Mai,
The face is pensive and lovely. There are, however, serious problems with this picture. I think you have the talent to be able to rectify these in the future.
A. Composition. Always secure your composition before you start a picture. That way you ensure that there are no awkward spots to fill afterwards. Personally, I would have put something square there, a picture, a window etcetera. Pastel is too messy to contantly rework. Know what you're about before you start.
I do large life-size pastels. I have to know what I am doing before I start.
There is an example of one on the
www.portraitartist.com site. It is under "other works for sale" (upper left hand corner) on the home page. Click on and scroll down to the bottom. It is the dancer with the red hair. The picture is over 7' tall.
B. Drawing. Her shoulders seem too narrow. The hand does not rest convincingly on her knee. The hand on the knee needs to be softened. Squint when you look at your material so edges automatically become softened.
C. Edges. The edges of her face, especially her jaw line need to be softened. Hard jaw lines seem to be rampant, even among professionals. If the jaw is too hard the head always looks like it has been cut out and pasted on.
D. Color. I assume you know your complementary colors. Since this picture is basically dull orange in color, it calls out for a bright touch of its complement, blue.