I usually don't

Lately I have been thinking how much I limit myself. I mean aren't we all guilty of it? I put these limits on myself, maybe for protection maybe just out of fear. It came out of context while I have been dating. I would think or say " I don't usually do this........" and then it wasn't so bad or scary afterwards. But then I started thinking, how much of that do I carry into my normal every day to day life? I mean it is real easy for me to think "Well no one has these expectations on me because I can't do this, or I don't normally do that" and when the opportunity actually arises I can do it, and maybe it should become something that I do more regularly.
How often am I able to take a risk, but don't? How often am I able to say, I can do this, but don't? How often can I make a difference even if its just a small one, but think to myself "I don't know how because I don't normally do this sort of thing."
Maybe what it really comes down to is that I am scared, scared that people may expect more out of me, and worse that maybe I will expect more out of me.