I Had Bad Cold/flu 8 Weeks Ago. Had Bad Cough.

I had bad cold/flu 8 weeks ago. had bad cough. saw my primary and said I had nasel drip in throat causing the issue and to take OTC decogestian. Now 8 weeks later I have been waking up in morning very congested in nose and throat, after about hour gets better, but all day and bnigth have scratchy throat adn feel the drip in my throat. Can this be an allergy or something with the cold that permanently did something to my nose/throat. This week has been real bad in morning