I could labor the idea but then that would only compromise the point. This article will have more impact on your career and psychology than any other business article you will ever read -- here it is.
The conundrum - are you waiting for someone to call you an expert? Even if others do, it won't hold near the weight, psychologically, that self appointment will. Experts call themselves experts and that is how they make themselves so. By declaration you declare yourself an expert. In the same manner humans declared this very country the "United States of America" sovereign and no longer under the order of England, you too can declare yourself an expert.
Think about the alternative, think about all the other things you can and do declare yourself that do nothing but compromise your success. Stop waiting and make it happen today. It will feel strange for a while but eventually you'll believe it too.
An expert is an expert when he or she determines oneself to be an expert. Only a lack of courage (which you also determine) will keep you from making an act of declaration with the power of words.
I find it almost comical that people will live their entire lives not really knowing why something is "so". It is so, because someone (a person, like you) made it so. Look at Donald Trump for example. He was born into wealth, went to the best of schools and still goes bankrupt every few years despite all his silver spoon experiences. However, others that start with much less than he did, never go bankrupt, make millions of dollars a year yet have to fight and claw to borrow a dime and not one tv producer ever asks them to do a show. The difference is, Donald Trump is the greatest business man on earth because he said so. If you don't believe me, ask him.