I would highly recommend Rick Jarow's The Ultimate Anti-Career Guide.
You'll find his personal story inspiring. He followed his passion and dropped out of Harvard, went to India to study meditation, came back & enrolled in a little-known college in NY, and got Ph.D. from Columbia.
Of course, it's much more than his personal story. Get the CD instead of the book, as his voice is very soothing & genuine.
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If you know your Myers-Briggs Personality type, you can get some hints here about career choices.
Common Careers for Personality Types
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Don't ask yourself what the world needs; ask yourself what makes you come alive. And then go and do that. Because what the world needs is people who have come alive. --Harold Whitman
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On the practical issue of money, since you're young, you can afford taking risks and living with little money while pursuing your passion. The opportunity cost will go up as you grow older. So it's better to explore, experiment now than later.
Give yourself a year or two to pursue your passion. It might lead you to something else.
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Also take a look at this:
Institute of Transpersonal Psychology
Pro: has a spirituality component to it. I don't know much about psychology, but I have a lot of respect for Carl Jung for his exploration of spiritual realm, which seems unfortunately missing in many psychology academic programs today.
Con: job-wise, you'll probably have to create your own career/job. Again, refer to Rick Jarow.
I'm not necessarily recommending the school, as I believe you can read all the books on your own if you don't need the degree. It mainly serves a pointer to psychology programs out side of the mainstream.