How do i know if i have allergies, a cold, or the flu?

Cold is milder: Inflenza really makes you sick, you have fever, bodyaches, headache, cough, nausea and vomiting, upset stomack, coogh and congestion and you really feel sick while common cold can give you milder symptoms like runny nose, cough , sore throat and sometimes slight fever and you do not feel that sick as you do with influenza allergies will cause sneezing, nasal congestion;itchy eyes.