Your skin texture is to monochromatic. Take a look at http://studioproducts.com/demo/palettxt.html I think, that you should add some highlights and shadows (under hair for example).
I don't think you should call it quits just yet, there's a lot more you can still do on the head texture. Here's a step-by-step paint-over example, I hope it's helpful to you.
Yeah, I used quite a bit of the color picker. I did this axe to practice painting the specific parts. For example I learned a lot while painting a the wood and etc. The texture isn't really done but I'm calling it finished. Gonna go back and try to finish my lady now :) And here's a gif :poly124:
Really awesome to see your progress! Definitely use some reference of shoulder pads or other models for lighting. I'd also suggest reducing the amount you use any textured brushes. If you want a clean, hand-painted look, I'd highly suggest sticking with the round and air brush. I'm not very familiar with Blender, but I'd…