is this portrait good? could i improve it?
It's good. Nitpicks: Maybe bring the ear closer to the face; that's a lot of cheek. The planes on the left side of her face aren't defined. Right eye seems too small. Maybe make the muzzle more pronounced. Philtrum seems a little off. I would emphasize the pressure of her hand on her face more. Also the whole image needs more values. Was this drawn from life? The rendering looks a bit hurried.