Andy said it right. People are too busy caring about their own chins to worry about yours at all.
A receding chin isn't anything much though, it's just the way you look. If someone is overly concerned by it, let them be. What you will find is that noone really cares, at least nowhere near as much as you will.
It's not your chin that's the problem anyways. You say your chin made you shy, I believe your shyness makes your chin. Your chin becomes an issue that your shyness can use.
I'm guessing what you really want is a way to overcome your own fears around your chin and to overcome your own shyness. The two ways are through self-acceptance and courage.