Good work, Max, with a good overall configuration and good progress so far, but it has room to grow richer and subtler. Just a few notes:
It didn’t affect other proportions too much (although it did make your face a bit narrower than his), but the negative space on the left is narrower, and the silhouette of his hair (and the shape of that negative space) is different. It might not seem to matter but that shape is sending a subtle signal about the foreshortening and volume on that side of the head.
Related to this, the darker marks inside the silhouette of the hair—especially those ones on our right—are telling an important story about the volumes and overlapping planes within the shape of the hair. Yours could be more specific and descriptive.
The shadow lines on the jaw should be wider and softer, and the shadow from his chin on his neck should be darker, which helps the chin and face to project more.
Your darkest edges—the eyebrows, irises, edges of the hair and shadows around the jaw and neck are too focused and hard. Everything in the original is fairly soft edged. Great job on the nose and ears in this regard, for instance.
His mouth is wider and upper edge of upper lip softer and less dark. Look for outer edges of mouth to be directly below the irises, as his are.
There’s nothing off about this–it’s good and very much on track but could go further.
I think that my drawing came out well. However, I struggled to emulate the way Picasso used his pencil. He made very dark long fluid marks that appeared to have been done in one clean stroke. I could not match the value that he created while maintaining the haste which can be seen in his mark. Also, the value on the face utilized smudging while preserving a textured feel which was something that I highly struggled with. I think I did a poor job with the eyes and keeping the hits of white in the hair that would have added depth and texture. Despite that, I am quite happy with the result.