All these symptoms can be a part and parcel of sinusitis or sinus congestion which can manifest as a result of allergies to air borne allergens.Sinusitis can cause headache,malaise and eustachean tube dysfunction also because of congestion of the sinuses with mucus.You need not be having any running nose or sneezing.
I would advise you to get your sinuses evaluated from an ENT surgeon.Transillumination tests,X-rays and CT sinuses may be needed to confirm the diagnosis.
Hope it helps.Take care and pls do keep me posted on how you are doing or if you have any additional doubts.
Thanks for your response.
I already had a Sinus CT scan done a few months ago that showed "mild" mucus thickening of maxillary sinus and deviated septum. My ENT said this was virtually negligible, but he put me on 2 weeks of antibiotics (Azythromycin) anyways, in case i had a bacterial infection. None of this helped my symptoms.
Do you think that my dust-mite/pollen allergies might be contributing to my "mild" sinusitis , and that's why the antibiotics didn't work ? But, even if the cause is allergy, shouldn't Nasonex (which I've been on for months), Astelin, Claritin, Nasal Irrigation etc. have eliminated by symptoms? Do you think it's worth doing allergy shots?
Again, I'm tempted to think that allergies is the root cause of all this, only because it's been going for over 6 months with no respite. On the other hand, my symptoms of headache, malaise and fatigue, and NO sneezing, itching, runny nose etc. makes me skeptical.
Thanks so much for taking the time to advise me. :)