What makes me feel old?
When my mind says I can do something and then my body says, "What?" or "You have got to be kidding!" or "You won't be able to stand up afterwards" or "Do you want to break your neck or something?" or, as he did recently, smallest DGS says anxiously "Don't break Granny!"
Most of all though is when you work out just how long ago something happened and it just seems like last year! 
As Luckygirl says it is an acceptance thing on the whole. We were talking to a friend who is retiring at 77, on his wife's insistence, and he really does not want to do it!
Liz I, too, have experienced the photos and the appraising examination! 
Tanith me too! It amused me this week when DD who is visiting for a holiday said she wanted to do exactly that rather than go out for the day! It is clearly not only an age thing. 
DH was rather taken aback when DD pulled up his face, to eradicate the lines and jowls, as Peter Pan did to Wendy in the film and said,"Oh, there you are!" 