Latest project of mine. Kinda wanted to do something totaly different but well, it just got to this. Hope you like it.
Hi, the head has strange proportions, it’s too flat or doesn’t have the depth in right places. Like eyes and lips. Skin shading is more like candle wax than skin. Less SSS and more texture. But I really like the hand and clothing.
I can’t really see the unproportional sadly, but I will try to fix it. Thanks for the critics 
apreciated
As bigbad says, and taking the eyes, for example, think of the skeletal structure. The eyes would be more inset, and not flush to the cheeks.
Take a look at your easiest reference, a mirror.
It’s also worth looking at primate reference to see an exaggerated example.
Nice modelling but work on beard and nose otherwise the background is good especially the shiny effect.
The distance between the bottom of the nose and the upper edge of the upper lip is generally a forefingers breadth. Maybe 1 and a quarter. It looks like your s 2. That was the only proportion I noticed on a quick inspection. Second, it looks like the window trim is cut from one piece, I recommend assebling it like real window, some of the wood will also be on the outside of the glass and there should be caulk and or tacks etc. Lastly the skin as they say, I’d add another shader with some bump, and imperfections. Try filmic Blender and play with lighting and move/rotate some of the bricks (create geometry where it matches the uvs) to make it interesting. There should be a lintel above the window I imagine.