Could you help me figure out what I have?!?

First off, I have a lower immune system, so I get sick easily. Secondly, I got sick in September with a really bad flu/cold. I was severely congested, had a fever, and then got pink eye from it. The symptoms finally subsided, but I haven't fully recovered. it's been 3 months and I am still congested. I wake up every morning, only able to breathe out of one nostril. My throat is constantly coated in mucus. I don't cough much, and I don't have the fever anymore. I just want to know what it is I could possibly have, so I can get better. Thanks!