uh oh, it's an oops! seriously, well done shot, altho i dont find that blue bg as flattering as some other colors might have been. I think it's that there's not enough contrast to really hit the spot for me.
An unusual twist on the challenge - desaturating the subject, rather than the background. But it works well in this case, and you caught a great expression. You did miss a little bit of blue around the shoulders that should have been desaturated to black and white.