I would agree with Jennifer's response. You can do a lot of things when you are a psychologist. There are many different types of psychologists, but most people think of a therapist.
Before you can become a therapist, you will undergo considerable training to prepare you. The training will help you develop skills that are necessary for the job. Personality is less important than your ability to learn those things that will help you do your job. As any healthcare provider, being a therapist tends to attract people who want to help others and who have considerable empathy.
Hope this helps.