I realize that you put much effort in making this pic, but there's still a lot to improve. My critique may sound harsh so remember that I'm writing this to help you.
Head seems to be too small, neck is too thick - put more time in making sketch. You need more Loomis (or Vilppu). If sketch doesn't look good, don't start rendering.
Why her front is bright, when sun is behind her? Easiest way to fix this is to put sun in a different place; some changes in shadows will be still necessary.
Grass in the foreground doesn't look right - you could do something more than just drawing lines.
If you're serious about learning how to draw read more about composition. In your pic it's not bad, but it could be better. Read "Famous Artist Course" chapter 3. Don't let title mislead you - it's about quite basic stuff.
Background looks really messy, it's unclear. I don't know what lines above mountains are.
Also to make darker lines press harder, or use softer pencil (I recommend B2 or even B4 for black places). Don't go over your lines multiple times, it doesn't look good.tl;dr:
You need more Loomis. Read this: http://www.squidoo.com/how-to-draw-learnhttp://web.archive.org/web/20130524085021/http://www.squidoo.com/w-ic-i