im still learning, plus these aren't like full scale drawings.
I usually draw the bottom only, like the nostrils, and just shade the sides, but I guess I don't go in far enough.
Noses r somethin' i have trouble w a lot so I practice them sometimes, ill get better eventually
for more like time consuming pieces i will draw a nose like this or smth but I guess I didn't pay to much attention to the pen ones