Are doing what you want to be doing?  If not, what is holding you back?  There is a Japanese term jitsuen (実演) which means, "To prove something by actually doing it."  Henry Ford said, "Whether you think you can or you think you can't - you are right."  So often, we look at something and our minds instantly say, "I can't do that."  This type of defeatist mentality keeps us from accomplishing  the things we want in life.  For me when this happens, I tell myself, "If someone can do it, so can I."  Before you say, "I can't" why don't you just try to do it.  You never know.  You just might jitsuen it.