I do not have problems with excessive nervousness, I have problems with anxiety. I get all panicky and mentally freak out and feel like I need to prepare for these things that are destined to happen to me.
A psychologist is ill-equipped to help you with this problem, but is well-equipped to convince you he's knowledgable and to take your money.
I would recommend researching this problem on the site fhu.com. It is most insightful.