The pose is a bit off, the hips should start at the bottom of the sides of the rib-cage, and her breasts are a bit misshapen. I'd also recommend not shading with airbrush-esque brushes, they don't really look natural. when painting digitally, most artists will have a set range of values, and will layer them in individually instead of laying in a really dark gray, and then blending it. Also, her left shoulder should be farther back, and the placement of her deltoid should be tweaked just a bit aswell. On her right arm her deltoid should be rotated back a bit, and you should be able to notice where her tricep picks up. You also drew her upper arm significantly longer than her left upper arm (accounting for perspective), her elbow is a bit broken as well. It's best to practice with figure studies before drawing from your head
http://img00.deviantart.net/1506/i/2015/340/2/c/female_body_study_by_tigrobobr-d9j7oyk.jpg