This is a life conduct question and you presented an important case to analyze. It involves lots of sub-challenges:
"I am an introverted person from my school"
Most Western societies and increasing other world culture are extrovert culture. They praise the extrovert ideals of speaking up (and loud), charisma, branding, impression, mixing with new people easily etc etc.
The most relevant works about the introvert/extrovert culture are
"In college I spent my time as an outsider with only a few quality friends."
Here I can see a possible future or current desire for belonging and being part of a community. As there are uncountable communities, groups and inspiring people to be in or with, one can change a lot of direction in pursuit of the people whom one can fully relate to.
"After masters is my period of self discovery where I was involved in different sports,yoga,music."
Self discovery and personal development etc, highly praised ideals in some culture and traditions, are no longer viewed as such in Western cultures and increasing other world cultures. Seeking a prestigious career, promotion, income, popularity etc comes first. Society expects us to follow them instead of self discovery and its related pursuits. That's again related to point 1 (extrovert culture).
"I easily gets bored with the job and I always thinking of me living peacefully in a small town teaching something."
However tempting that may look, isolation from society and not leading a life of action does NOT help self discovery itself, especially during youth years. Self discovery and self actualization, to be really solid, permanent, teachable, published, tested etc, have to be in a context of life of action and being with people interacting, exchange ideas, seeing the differences and reflecting on them, socializing etc etc.
"I still feel I want to do something else."
Self discovery can be attained in virtually every context and situation in the real world. The more challenges and stimulus you face the better esp. with people."
"For me money and property is not a big motivation factor."
That also related to introvert/extrovert question. In Cain's book, she also traced that trait to biological roots too.
"I just want to know whether it is a normal thought for everyone who want to pursue their passions or is it some mental problem?"
Plato: "An unexamined life is not worth living"
TV: "There is no such thing as examined life"
Edit on 2013-07-01 10:18:
I think I should summarize my answer to directly answer the question.
Your self discovery can help you
- find your passion(s) in life
- where you can excel at the most
- where you derive your life purpose and meaning out of it
- be part of a professional community
, even if took some years to arrive to a clear path.
Then, focus on it exclusively, direct all your effort for it and, at the same time, be content with it. The trick is to combine ambition to excel and to grow with contentment with what you have and reached (it's easier said than done).