Hey, man. Nice first attempt!
I'm not gonna lie the proportions are out on this. And the general shape of the head is off. I would suggest looking at lots of head photos (even your own) and studying the shapes... though I will advice you use actual human reference for modeling your heads. Of course if this is going to be a cartoon style model.... no probs.
If you need reference.... just let me know. I have TONS of head reference. Actual orthographic photos of peoples heads.
Nice work!
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