Seas' journey into the unknown

[Tom Seas]

Did my first portrait from imagination ever, could use some help, here what I think is wrong with it:
the head shape feels like it doesn't belong with the features somehow, maybe it's too broad?
The mouth kinda looks flat
I'm not sure about the shadows, looked at some faces to get an idea of what to do
I tried not pushing the whites/blacks but you can't really see the 6 dark accents.

Also some nose studies. Finding good ref is impossibly hard :l