Hi Elinnea- I like you painting a lot it has a nice mood to it, and i have utmost respect for anyone who can paint as well as Cym and you do with a mouse-if you can master that the way you have you can paint with anything it a great skill to have.
I agree with AgedP and Drzeller that a bit more contrast will really make the facial features stand out more....if your nervous about wrecking the painting why not make a copy of your work saved under a different name and mess with the copy...that way you can be bold and try crazy stuff and if your playing changes the painting in a way you hate you can just bin the copy and you havent hurt the original work
"I like to have a thing suggested rather than told in full. When every detail is given, the mind rests satisfied, and the imagination loses the desire to use its own wings."
~Thomas Bailey Aldrich~