First,
The sore thumb is the feet. Since your practicing on backgrounds, i would rate the background fairly well, the lighting is good, what detail is there and the artistic style is fairly well done. Just the shoes are driving me insane, more so her right foot than anything, I'm constatnly drawn to how it looks like it's crooked weird to show the side and the full bottom of the shoe at the same time.
Also, the arm, IMO, the right arm that is, is drawn extremely skinny, almost as if there were no muscle tissue, just skin and bone. Something more proportionate to the rest of her body would be better. The arm itself is proportioned correctly, you just need to up the size of it.
The hair color, i like the brown hair, but for some reason, i keep telling myself that it doesn't quite fit the atmosphere, i can't quite pinpoint what it is, but it just seems like it's not musky enough or something.
On her right leg, where it meets the shorts, it seems as if the leg is painted on top of the shorts instead of coming out of the shorts.
Her upper leg position seems reasonable, it does suite the atmosphere, the knees look a little funky, but okay. The lighting on the right knee does seem a little off.
What i do like about it though is the lighting going through the trees, the background, and her clothes (beside the shoes).
Don't take a critical review as a bad sign, just look at these things yourself and see if you can improve on your next piece of artwork.
Generally, when i make a serious review, unless I'm completely astonished with the work, I withhold 10's. Keep up tthe good work, i like your style, don't get my review wrong, i do like this picture and you do have potential as an artist, I'm just trying to help.
6/10
3/5