Good questions. I wish someone had answers! I don't think there's one thing we're "supposed" to do. We just have to try out the things that interest us and see where it takes us.
Most people have several careers in a lifetime. I went through a year of medical school but didn't agree with the focus on drugs. So I finished a degree in computer science and worked as a programmer. I was laid off during the technology bust and heard the healing professions calling me again, so I chose massage. At the time I was also trying out new age spirituality. I quit after 5 years because my experiences and beliefs changed so much that I don't believe in new age spirituality or massage any more. Now I do programming projects for small businesses and I'm enjoying life once again.
I have a business background and made good money in massage, but most people don't. People who don't want to start their own businesses make around $20,000 a year. About 95% of all massage practitioners burn out or become injured in 3 years and quit. Statistically it's not a good or safe bet.