A very good job on color and tone! It's a great piece.
The only actual criticism I have is that, while some parts are intentionally left blurry (shoulders, hair, etc.) some parts of the drawing would have been much more interesting if you had used a sharper brush. The eyes, eyelashes, and the interior lining of the lips would have been more appealing with some sharper edges!
Great job nonetheless, and bigger props for doing it in under 3 hours!