get a referal to an ent doctor, sounds like an internal auditory canal issue. do you get ringing in your ears? thats tinnitis. what cts did you have done, most likely brain. if you havent had iacs ct or mri, your ent will order it. it could be related to your sinus inf 6 mos ago.
I had similar thing. I had inner ear infection and was treated with antibiotics, but headache remained. I had MRIs and nothing showed up. Went to chiropractor and had an adjustment. I am now headache free.