All perfect praise be to Allaah, the Lord of the worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad, sallallaahu ‘alayhi wa sallam, is His slave and messenger.
The greatest way to achieve self-confidence is to be pleased with what Allaah decreed on you and not to belittle the blessings one enjoys. Also, a person should be certain that regardless of how bad his condition is or how much he is afflicted, there are always people whose conditions are worse and are more afflicted. If he remembers this, he will praise Allaah for his condition and he would know that he is greatly blessed.
It is for this reason that the Prophet, sallallaahu ‘alayhi wa sallam, encouraged us to always look to those who are inferior to us in terms of worldly pleasures, and warned us against looking at those who are superior to us, so that we will not belittle the blessings of Allaah on us. [Muslim and others]
Hence, if a person looks at those who enjoy worldly pleasures more than he has, he will belittle the value of the blessings that Allaah has given to him and will envy the blessed ones for that, but if he contemplates those who are less privileged, he will be content , pleased and thanks Allaah.
Certainly, if you are embarrassed because of having your nose bigger than normal, then if you were to look to people who were born without it in the first place, or one who has a deformation, or a great disability, like being deaf, blind, or mad, etc, you will surely feel reassured and pleased with what you have and realize the great blessings that Allaah has given you.
Allaah Knows best.