Help me find my faults in this Character's Head

[Famouz]

Ok, this head should look a ordinary face with nothing special in it. just looking like me and you.
So that's what I ended up with:
http://www.abload.de/img/headpxdo.jpg
http://www.abload.de/img/head2y9uj.jpg
http://www.abload.de/img/head3rbmi.jpg
Please help me find the mistakes I made that make this head look "wrong" and unnatural.
I'm very happy to read your comments and I will learn from everything you'll teach me.

[jocose]

Skull is too small the face and depth of the skull should be equal in length ideally. Not sure if this belongs in technical talk either might want to try pimping and previews in the future or general discussion.

[Jaco]

Eyes are a strange shape, pretty much lidless and don't conform to the spherical shape of an eyeball (lack depth). Edge along bottom of nose is too sharp, no nostrils, also no definition around the nostrils. Mouth is too flat, from the side the upper lip should protrude further than the lower (in an average human at least). Cheekbones are too defined.

The proportions of the head and features are fine, you just have to spend some more time refining the features, using plenty of references of course.

Here's a quick paint over that should help.

http://img.photobucket.com/albums/v332/Jacoh/FaceOP-1.gif