I have allergies that affect my throat and I do take claritin and benadryl which helps but ive also had infections in throat, how do I tell the differ?

Allergy vs infection. True soreness of the throat would be unusual for an allergic reaction, but favors infection-either viral or strep. Development of head cold often follows a viral sore throat while strep doesn't produce head cold symptoms. Throat allergies often cause itching, watery eyes, nasal congestion with clear mucus.