People who would never think of trying to drive a car with the brakes on often do something very similar to themselves.
 
A wise and funny woman once said, "Show me a person without guilt, and I'll show you a person without a mother!" Now, she herself is a mother and guilt, when it's appropriate, is a useful function of a healthy conscience. 
 
The point she was making through humor is that allof us suffer from at least a touch of guilt and feelings of unworthiness. When these feelings grow large enough to take over, it's like trying to drive a car with the brakes on. You may go forward in fits and starts, but you won't go very far. 
 
Guilt and unworthiness are things we were taught to feel as children by misguided adults who probably didn't realize the damage they were doing. By the time we became adults, these feelings were so ingrained that they became automatic responses - part of our self-image. 
 
That's the bad news. The good news is that you can take yourself off automatic and bring your consciousness to bear on these feelings. You can learn how to refuse to accept unearned guilt and forgive the people who foolishly taught you to feel unworthy. Chances are, theytoo were taught that way. But you can break the cycle. 
 
A commitment to do it is a great place to start. Seek out resources - counselors, teachers, friends, classes and books - that can help you feel the peace and personal power that is your birthright. And stick with it until you get there.