multiple things can cause this syndrome .
allergy is one of the causes.
but it could also be a viral infection or a bacterial infection.
if it is allergy you should expect it to be seasonal or climate related and usually is recurring. usually you would also
have itchy eyes even a running nose. you might sneeze but you won't have any
fever.
if it is a viral infection yes you could have all these symptoms but usually you would also expect to have a bit of running nose, itchy eyes red eyes, some
cough or
chest irritation.
if it is bacterial in cause then we need a treatment but how do you tell it is bacterial? if you feel pain when swallowing or you feel pain in your neck ganglions then it is possibly bacterial. you could also have some
otitis media which is inflammation of the middle ear.
if it is allergy you need to avoid the allergens
if it is viral just take lots of fluids and get a pain killer
if it is bacterial you need a course of antibiotics so you need to see a local doctor for consultation