I have major insomnia and fatigue 24/7, can I get a CAT Scan of my brain?

I want to see if anything is abnormal. And if there are some lose wires there (which I know there are) I need this proof to show to the doctor who doesn't believe me and refuses to give me narcotic pain killers to ease my suffering and put me to sleep. I am really suffering here. I had a cat scan when I was a kid but not one since. I don't recall it showing any abnormalities. Would it be a good idea to take this again??? To detect if I am suffering from insomnia and fatigue and pain??????? Please don't annoy me with answers like try milk and cookies or whatever. I've been suffering for years and nothing works. That's why I'm asking this question!