Good job, but I know you can take this further and thus some crits, mainly regarding proportions.
Her:
- Nose is too wide, look at nose/eye width ration in photo.
- I think her jawangle is steeper than 45 degrees (which is the lazy way to go here).
- Her jaw also is not as wide, I would shave off a few pixels on the side.
- I think you made her too shiney, she looks greased up.
- Her nostrils look a bit harsh.
- I think her lower lip could do with 1 pixel more thickness.
- Folds around her mouth too harsh, make her look older.
- Neck could be rendered a bit more.
- Her hairline should be a few pixels lower I think.
You:
- You made your mouth a tad too wide.
- Your left eye is quite a bit higher than your right, and at this size you can show this for sure (I have this too, asymmetry ftw!)
- Eyebrows too big, look where they stop over your eyes, you made them go too far in.
- Birthmarks, moles, whatever on neck and forhead, perhaps even the ones on your left cheek.
- Neck could be rendered a bit more.
I think that's it for now.
PS: Nice girlfriend.