Linda Ann’s Answer
The three careers that you mention have VERY different educational requirements. Perhaps you should enter college as an undeclared major and explore differnt courses to help you to focus. ALSO you could have conversations with your academic advisor in college for internships during the summer months to gain access experience to help you to decide.
A physician assistant (PA) requires very specialized coursework and probably 5-6 years of educational credentials.
To become a psychologist you need a doctorate; the time line is at least 9 years of education (4 for the BS plus at least another 5 for the doctorate). You need to be licensed in the state in which you wish to practice which may require more credentialing.
You should explore the website of the FBI to learn about their educational requirements for entry into their academy.