Persistent Cold Symptoms: Possible Causes & Next Steps

Question
hello, i am sorry if this is a little long. for the last 3 months i have had a bad "cold" congestion, headache, sore throat,mild cough, mild diareah and occasional hot/cold spells. i have been to my pcp 4 times also an ent , i have had numerous throat swabs, a sinus ct, a blood workup,allergy tests and a mono test 3 times. all came back normal. i have been given 2 sets of antibiotics and entex for congestion with no relief. my question is are there any other diseases that present this way? when i search online for my ongoing symptoms all i get is hiv and some forms of cancer. is there anything elese i can have my doctor check for? i fealt better last week for 2 days but its back again. i am a 25 yr old female with no known health problems. thank you for your time.

Answer
if it has gone on this long, it is allergies, not infection.... that should have long since gone... I would use oral antihistamines (claritan) and nasal steroids like flonase for symptoms.... but it sounds like this is more like chronic allergies.......