Well done. This is excellent work. I am qualified to say that because I was a portrait artist. I can tell you are very passionate about your art. Wisely you have drawn your subject large enough to work out all the small details. If I could make a suggestion to help your process, when I was drawing portraits, I built a small bridge, the size of a large ruler, with feet at both ends. I wish I had a picture to share. It was a hand rest that kept my hand about a centimeter from the page, but made it so much easier to draw in pencil, without ever touching the page and smudging my work with my hand.