Nice work here. I like what you've done here. The color really pops and it's quite nice. A behind the ear tattoo photograph is never easy to take, not that I would know!
It's hard to critique this without knowing your desired application for this image. One word of caution is to be careful with your hair selections. Selecting hair in photoshop is about one of the most tedious and difficult things you can do in photoshop.
If this is to be blown up and printed as a poster you will notice the selection really stands out:
This is a common theme with photography actually. It has to do with something very technical called the [urlhttp://en.wikipedia.org/wiki/Circle_of_confusion]circles of confusion[/url] but a simple rule of thumb is that the bigger something is blown up the more perfect the image needs to be from a technical standpoint. In other words, if your image is going to be on a billboard or a large print you want to be sure to nail your focus etc etc. The bigger something is, the easier it will be to see the flaws.
There is another technique for selecting hair in photoshipp using channels that is a little bit more advanced:http://planetphotoshop.com/select-hair- ... nnels.html
I like that you have used photoshop in a relatively colourful and vibrant way and yet you've also done so with nuance and subtlety. Just be aware of the detail of your selections in the future and as always try to shoot the image you want in camera and then augment your image in post processing after the fact.
Nice work here.