(just used this one)
Insist everything is Fine, despite food on sleeve, hair in disarray (on grounds that if one is able to pretend everything is fine, it's probably close enough to get by on).
Cry, or yell publicly, or fall asleep with mouth open while drooling, or faint dramatically (to see if sympathy can be garnered from some quarter and/or, more interestingly, to see what will happen if I openly manifest an inability to look after myself? Possibly nothing much).
Responsibly, silently, alertly, professionally, uncryingly grade essays in office with view onto a grey stone wall and wonder if the sun will come up tomorrow as Annie so plangently promises in her lyrics.
(now) Go for a walk, dammit.