Multiple UV texture issue on figure

So this is the situation.

I followed a tutorial on blender cookie on how to UV unwrap a female figure. I did this on a model I made.
It involved unwrapping the head and then unwrapping the body. Thus having 2 UV maps for one figure. Works a treat. I managed to work out how to assign materials and 2 defuse maps to the model so that they appear together (something the tutorial didn’t cover) originally I could only see the head texture (if the head uv was selected in the object data tab) and not the body texture, and the same if selecting the body uv. But as I say managed to figure that out.
But, there is a problem I can’t seem to figure out. Now that I can see both together, if I select the head uv in the object data, the detail in the body texture seems to appear different. Clicking the body uv will sort that problem, but then the head detail appears wrong. Having played around with it, it’s clear it only the normal maps (in the textures panel) that it’s effecting this issue. If I switch them off everything seems fine. But obviously I want the normals on there. What am I doing wrong?
Also, when I do have the normal maps on and select the head uv, the head is in complete shadow. If the body is selected, it’s fine but the head still appears quite dark. Looks fine with the hemi light but with the sun it plays up.

If anyone can help, I,d be so grateful…

Sounds too complicated to figure out w/o a file but for starters at least tell us if you are using Blender Render or Cycles.