The chances are if you are asking this question you need to see someone. You would see a Psychiatrist mostly for medication. A psychiatrist is a medical doctor with a specialty in psychiatric medications, though I have known one or two that were pretty good counselors as well.
Psychologists focus normally on testing or a diagnosis, though they often do so therapy as well. What you may need is simply a therapist, somebody to talk to and help you sort your thoughts. Seriously, it all depends on what your needs are. Does that make sense? If you need more information, pleas elaborate and I will do the best I can.