[Silent Night]

Okay, I tried to keep as anatomically correct as possible, though I think I might have made mine's muzzle slightly to thick.

I have a few pointers for you, I might not be that great of an artist but I have studied anatomy a little bit.

• Eyes:
  
  1. Your eyes drawn appear to be to large for the pictured head, I do realize it is a style of art, but if trying to draw anatomically correct you should probably size 'em down a notch or two. ;)
  2. Eyes have a different shape when viewed at a side angle, the are much more triangular in shape.
     
     Side view (http://www.123rf.com)
     
     Front view (greyiscolour.wordpress.com)
     
     Notice the difference in the eye shape? The ones you were drawing more resemble a dog's eye at front view.
• Muzzle and nose:
  
  1. Your muzzle is very small height-wise and should be a bit thicker.
  2. The bottom jaw of a dog usually shows very little if at all.
  3. The end of the dog's mouth should line up with the inner corner of the eye.

I might add a few more tips later, but I'm getting kind of tired :P .