Sore throat and painful swallowing with headache and body aches. also sufffering from allergies, are these things related? if not, what's causing it?

Possible: The symptoms are more compatible with a viral upper respiratory infection than allergy. Painful swallowing is not typical for allergy and is more consistent with a viral pharyngitis. All your symptoms of headache and body aches and sore throat would be viral in etiology. Fluids, pain meds and time.

This time of year: Anything could be possible. Strep throat, flu, sinus infection and allergies or combination of the above. Best to see your doctor for disgnosis and treatment before it gets worst. In the meantime, you can take tylenol (acetaminophen) or Motrin etc and allergy meds like allegra, Claritin and the like.Drink plenty of fluids and bed rest is essential.

Secondary sinusitis: If your illness started as an allergy and now you are sicker and have started having a sore throat and yellow discharge, you probably have a sinus infection that is caused by your allergic swelling blocking the openings to your sinus cavities. Once you cross over from allergies to a sinus infection, you should avoid antihistamines. They dry your secretions and make your infection last longer.