What is the difference between confidence and over confidence?

With example I am explaining this.

Suppose we are working with a team, so According to me,

Confidence is yeah surely we can do this (speaking positively & calmly).

Whereas.

Overconfidence is only we can do this no other people can (speaking loudly i.e. in different tone or we can say rudely also).

This emotion given in brackets also matters while answering.

Confidence is I am perfect in this field.

Over confidence is no one is perfect than me.

Confidence is something that will help you to achieve something. Confidence is I can do this task.

But over confidence is I'm the one who will do this task.

Over confidence may lead to decrease your performance. Dreams will be only dreams. It won't come true.