Damn, I am so intrigued. You did that with a mouse?
Don't get lazy and just c/p without fixing lines (under jaw, hair on forehead, top/back of head).
Depending on hairstyle, sometimes curve the hair to fall straight vertical. This will fix mapping for back of head.
Beginning of hair on forehead/next to eyes/ears has nice texture and volume. After this, hair turns to mush. Replicate prominent light source, use to create shape and volume.
Not all hair needs to be touching its neighbouring strands. Disperse sometimes. You will find it adds character - similar to "Beginning of hair on forehead/next to eyes/ears".
Ears disappear? Differentiate from jawline/chin shadow.