How to come off as an insecure douchebag

A good rule of thumb:

When I tell you how impressed I am with a mutual friend or colleague, and you respond by:

Telling me why I shouldn’t be impressed
Talking about yourself
Telling me why I should be impressed with you

… then you come off as an insecure douchebag. Which you probably are.

Is this something only I experience, or is this a tragically common occurrence?