|A friend of mine tried to make a joke calling me "old."|
Since I worry about aging, I didn't take this "joke" well. I call this "other-deprecating" humor as opposed to self-deprecating humor, where you make fun of yourself.
I have a very cracked screen on my phone. When people ask how it happened I say I was taking a selfie and it cracked.
Tell someone a self-deprecating criticism about yourself or your group and see how the person reacts. If the self-deprecation confirms what they might be thinking they'll react one way.
You can determine what to say to others and what not to by the way people's comments make you feel. Angry? Then don't use it. Happy? Feel free to use it.
A co-worker says "You're so funny," after I made her laugh. This makes me feel good, so I'll use it.
Calling me "old" and I felt bad and liked the person a little less.
Some "old" people will be okay with being called "old." But others will not. So before you open your mouth, think about the consequences of what you say.
It's interesting that the word "consequence" is "con" or opposite plus "sequence." Which is the action to the sequence is opposite to what you want.