What can I do for sinus pressure so bad that it hurts to tilt my head?

AFrin (oxymetazoline)? Before you see your doctor, you could try afrin (oxymetazoline) nasal spray--follow package directions and avoid usage for more than 2-3 days at a time. Saline nasal spray can help. Oral decongestants such as sudafed may help--follow package directions. Once you see the doctor, they can evaluate and manage your condition and provide any prescription treatments needed.
See a doctor. That type of pain is unusual for "sinus pressure." if you have a sinus infection, i'd be concerned about a complication or extension of the infection. If you don't have a sinus infection, i'd be worried about something irritating the lining to the brain.

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Chest congest harsh cough for over week, some fever w/it. Seemed to be clearing up, now coughs hurt head, lots of sinus pressure pain see doc?

Possibly. You are getting to the point where you may need to see the doctor but if you are indeed improving try first to rest and very hot fluids to clear the sinuses like hot soup. Try this first.