Awesome, but some problems
The first thing that I noticed about it was the way she was leaning. If this were a clip, it seems in the next couple of seconds she would be falling over backwards. There are no elements in the foreground to show that this could just be from a certain angle.
The other issue I see is the length of the arms. They are just a tad too long for her body. Most peoples palms reach the area of the hip-bone, it looks like hers go about four inches farther than that, making her arms look a little off.
Now, I'm assuming this is a fantasy piece, so I can imagine this a possible non-human race, meaning they would be made differently and the problem I previously spoke about isn't a problem any longer.
The shading is nice, and I love the way the leaves have a feeling of movement in them. You did very well with that. The sky and the trees give this piece a sense of ominous dread, like something bad and/or difficult is coming up, and the look on her face and her body language support that.
All in all, great work. Keep it up!