portrait sketch of the day

I don't think there's enough structure to the eye/eyebrow area. 
Also this may be personal preference, but the overall image is in a mid range of contrast, Something to keep in mind is that the dark parts of (any drawing but especially portraits) is always darker then you'd think. 
Don't be afraid to go really dark in areas and highlight others. 
Good work!

Love your drawing! Your shading and detail is also awesome. I think that the eyes are a little off though, that is the most noticeable thing. Maybe some guides for the eyes and facial shape during the sketch phase would be beneficial! Awesome work!!

Thx for your encouraging Feedback. I also colored the drawing later, it kind of grew on me after some days with all its inperfections. Here the Link If you are interessted.

https://imgur.com/a/ucY4MZr

I struggle a when a model hast very strong drooping eyelids... for me that is hard to do or see in the drawing...