You could have sphenoid sinusitis, but it could be something else. Not much you can do until you go to the ENT and get an ENT's view of your problem. Never ever accept the "psychological" explanation, and never give up.
If it turns out to be sinusitis due to an chronic infection, and you are unable to remove it by conventional means, I have developed a different sort of sinus irrigation:
http://www.medhelp.org/user_journals/show/2322
The Flip-Turn Sinus Flush is mildly risky, because you have to bend over to do it, preferably in a shower, but you can also do it outside on soft ground.
Neti pots and other sinus irrigations often don't work for sphenoids, because gravity intervenes before saline can get that high in the head.
However, do not bother to try it until you have visited the ENT. In the meantime, a Vicks machine in your room overnight works pretty well.
Even though your symptoms look like that of a chronic sphenoidal sinusitis its always advisable to get a CT scan done to confirm the diagnosis. Meanwhile you can take Mucolytics (like bromhexine/ambroxyl) and do steam inhalations 2-3 times per day.
Regards
OHNS2010