It's funny, I'm the opposite. I'm a furry artist who finds human faces easy and animal faces very difficult.
Gorgeous shading on this piece by the way. Nice to see well defined facial structure on an anime style character. I like how you used soft gradients to give dimension, with nice sharp edges that separate the different forms; that's hard to pull off with low-contrast color pallete lineless art like this.
My one suggestion for improvement would be to give a little bit of texture, perhaps with some kind of stippling or paper grain effect, because the perfectly smooth face does look a bit doll-like