You may be meeting people or even friends who sometimes hit at your self-confidence and try to deflate it. It may be a joke on you or criticism of your ability. Mostly they do it unintentionally, and sometimes intentionally. It is integral part of our day-to-day life and nobody can escape it.
If such a thing happens several times you start feeling pale and weak inside. A self-doubt enters your psyche and it influences your performance negatively.
And dear friend, if you do not keep mending the confidence-deflation it may prove serious obstruction on the way to progress or achievement.
As soon there is a hit on your confidence prepare a counter hit, not for the person but for the statement that hurt you. Keep telling yourself that your are capable. You can do the things. People may not be understanding you properly, but you have the ability to achieve.
Such a self-talk will keep your confidence alive. You can also develop the habit of reading confidence-boosting books and articles at night ( just before going to sleep).
Thus, with your own efforts, you can become immune to destructive forces.