If the pain is in the eyes or centered on the eyes then I would think "exposure keratitis" or "recurrent corneal erosions" both of which you can read about using the search feature and archives.
If you'vehad it 4 years and it hasn't got worse and nothing new developed that's a good sign. Other things to exclude sinus disease (see ENT) and blood pressue problems.
JCH MD
For four years I have an eye problem, I would go to bed feeling good and would wake up in the morning with a sharp pain at the top of my eyes close to the sinus area and a head ache this happens to me like twice a week, I've went to two optamologist who can't find any thing wrong with me, any suggestions.
A common cause would be a pinguecula but you will need to see an ophthalmologist to get an exact diagnosis.
Find one at www.aao.org
JC MD