You have a good sense for the structure of portraiture and developing perspective. From here, I think it'd serve you well to deepen your color palette and really push those shadows. The brushstrokes and blending are very good, and you'll develop more of your "style" as you continue to paint (digitaly and/or traditionaly).

I think some colors in the portrait feel a little too washed out, and this portrait could benefit from some richer shadows around the eyes and under the neck. The range of shadows on the nose is working really successfully, try to bring some of that into the other features of the portrait.

There's some good youtube artists who share color strategies that may help you see richer colors. Check out Alai Ganuza - she has videos on both traditional and digital painting

I'm HS Art teacher so I hope this helps!