Hi Mytri, following are a few books which can definitely help you in increasing or boosting your confidence:
1. Outliers: The Story of Success – By Malcolm Gladwell
2. Bounce: The Myth of Talent and the Power of Practice – By Matthew Syed
3. Feel The Fear And Do It Anyway – By Susan Jeffers
4. The Chimp Paradox – By Prof Steve Peters
5. The Happiness Project – By Gretchen Rubin
6. Failed it!: How to turn mistakes into ideas and other advice for successfully screwing up – By Erik Kessels
7. Happiness: A Guide to Developing Life's Most Important Skill – By Matthieu Ricard
8. How To Stop Worrying And Start Living - By Dale Carnegie
9. Thinking, Fast and Slow - By Daniel Kahneman
10. If You're So Smart, Why Aren't You Happy?: How to turn career success into life success – By Raj Raghunathan