Confusions deduced

I was always confused on this very topic and I thought one day it will work out doors for me to success.
A friend of mine said
"if u dont have
confidence over
confidence is just not the
case" when I was acting a but weird on a friendly revolving chat.
So what actually is it.confidence what they say is self faith.putting it in easy words.when you go out their singing in front of people for first time and someone says just have faith in you,he's filling you with confidence and when you go out their and sing with your body shaking like anything that lacks confidence.well that was a incident from my childhood.so where does over confidence comes in play?what if that kid before going to stage had thought this I am the best I know and I ll let them know.well that's this.more importantly over confidence is a rare adjective in people with good heart.If you have a heart that's gentle and responsive quiet very soon,don't run in dilemma of what is it.of course it will be confidence my friend.
Sometimes it needs just to over come this confusion to come across a new road.