It looks alright but there just isn't enough detail for me to really like it. If that is what you wanted then okay that's fine. Then of course everything InsertFunnyNameHere said is right, your lighting is consistent, I have no problem with some of your shading (excluding the light issue). I think you could have done better though.

average

not anything too interesting needs more sex

Contrast

There isn't enough contrast in the shading. This leads to the features blurring together but mostly, it just doesn't look alive and realistic enough. Put in a few more splashes of shine and then darken the shadows by a lot. Also, use a wider range of tones as opposed to different shades of the same few colors.

Your direction of light isn't consistent. It isn't coming from the left enough on the rock and her hair doesn't have any direction at all.

There are proportional problems, as well. Her arms are too long and her face looks smaller than it should be. Also, there's something very wrong with the way that her left (from out perspective) leg is angled. It looks like it's broken. The leg is also too long. If you aren't already using a reference, then you should almost always do so.

My last comment is that you have fallen into the trap of the smudge tool. You should never use the smudge tool to shade unless it's something very subtle. Use pallets of color instead.

not bad

I can see a little of what you might be talking about in the hear: it puffs out around the face like a cobra then the bottom strands split oddly. Other then that, you have the right amount of casual nudity to not be lame, which is nice.