What Is The Feeling Of Headache Accompanied By Dizziness And Nausea?

from time to time I get this feeling like a headache that never really kicks in its just there. Its usually accompaied with slight dizziness, nausea, and sometimes a weird smell like a face full of ash tray, I also have a hard time focusing my eyes. This usually only lasts a ay or two but going on a week this time starting to get worried. I am 43 male 245 lbs and 6'1"