Several symptoms

For quite a few years i have had sudden pain in my head that lasts for just a few seconds. Never thought much of this until other people told me they have never had anything like this. Three years ago I started getting an aura of smelling nicotine with sleep deprivation followed by migraines for several days. Recently i started getting sudden dizziness while sitting at my desk which only lasts a few seconds. I am not sure if these are all related or different issues. I did suffer a concussion about 20 years ago with nerve damage to my ear, but i honestly doubt these are related to that injury. Anyone else have these symptoms?

I went to the doctors for the nicotine smell that I get prior to migraines and they wanted to do a CAT scan, but I never did that. I am a bit claustrophobic. The weird thing is I have never smoked and am not around anyone who does so not sure why I would smell nicotine. It is especially bad when I fly and lasts for days prior to the headache.