Are we to take it that this is a base mesh for further sculpting on? if so I’d say it’s a little heavier than I would start with… the ear for example might become a bit too twisted as you bring out the forms more…
it’s better for sculpting to have a more uniform patch size…
if you plan on subdivision modelling then this is a good start…
compare the profile of your model from the nose down to your reference picture:
the chin is more defined and further back in the ref, the bottom of the ear is further forward and the fore-head rakes back more dramatically.
the internal structure at the mouth corners is pinched flat rather than “turning inside” the mouth…
it looks like a circle squished vertically… think of the lips as the inside ring in a torus… when closed the patches still have depth at the corners!
you may want to pay attention to eyelids.
the mouth is probably a little narrow from the front (the corners of the mouth should line up with teh center of the pupils from the front…
Hope those helped!