We tend to think that the ideal manager is something that leads other and has special gifts in doing these. It’s one way of looking at the issue. The other is self-management, and this includes without being limited to these qualities: emotional balance, integrity and – yes you are right – self confidence.
There is a right emotional balance somewhere in the middle of being a stoic and being ready to shed a tear. You are human and you should show this to some extent. Be expressive but understand that you should convince. Integrity is also essential for the leader, and this is related with gaining trust and credibility. Practice integrity and you will manage better.
Self-confidence is the hardest skill to master. It doesn’t come easily and it’s lost in a second. It depends on knowing your strengths and trusting your guts. This almost never fails even though you will find yourself more than once in the position of questioning yourself and your actions. So, just, take one step at a time and you’ll be fine.