Try not to use all three colors red, blue and green in the same texture. It usually doesn't work very well. On this, the colors are spread out so it's not bad but just FYI for future purposes.
I would either add more color to it or take out the red and blue thing on the back.
Shading could be smoother too.
It's a good first head though. The mapping is good especially for a first head. Keep it up.