Am i right?

Everyone has a weakness, right? Well, mine is very well hidden. They say, I show no fear, very little emotion and always seem to be levelheaded. I am said to take most things in stride and don't' worry much about anything. I am not afraid of heights, spiders, close spaces, black cats, or thunderstorms. Does my attitude tells everyone that they wouldn't want to meet me in a dark alley. My only weakness is in my Achilles' Heel, but this is a well-guarded secret. (Shush!) We'll just keep it between us. Am i right?