How can I overcome doubt ?

It is ok to doubt yourself .Doubt will bring sense into you – for you to see whether you are causing what is happening around you. If your psychological growth is one step ahead of your physiological growth – then you will not have growth pangs. Right now, people are living as if every stage of life is a problem! Life should not be a problem, it is just a certain process – its about preparing oneself to manage that process.