After undergrad, I went to graduate school to become a school psychologist. The background from Duke psychology classes enabled me to be successful there. While at Duke, I also designed an independent study course that included weekly shadowing of a school psychologist in Durham Public Schools and a literature review, where I was able to correspond with Dr. Ken Dodge and his research.
While it's not impossible, a degree is psychology alone is unlikely to land you a job in the field. By the beginning of your junior year, I would advise going to the APA website and browsing through the different subfields of psychology. Start to narrow down where you would like to focus, whether it is clinical/counseling, I/O, sport, etc. Duke offers great flexibility with coursework, so if you find that existing classes are not as specific as you would like, find a way, such as independent study or working in a research lab, to earn credit or money while exposing yourself to your career interests. When you start to evaluate graduate programs, first make sure they are fully accredited or approved by the relevant professional organizations (e.g., APA, NASP). While programs can offer degrees without being accredited, the program is likely not as strong, and your licensing process will be more difficult. http://www.apa.org/careers/index.aspx