What could I possibly have...?

I had sinusitis twice in the past month and a half. The sinusitis is cleared, there is just a lot of mucus build up (white) in my nose and it's a bit runny. However, I have had a gradually worsening cough for about two weeks now. I cough up thick white mucus and occasionally green/yellow bad tasting mucus. This morning i woke up and sat down on my cough and i started inhaling and exhaling through my mouth and as I did that, I felt a strange; fluid feeling... kind of a wheezing... in the left side of my chest/lung area. I used a stethoscope I have at home and I heard wheezing on the left side by my lung. Now, I have quite a bad back ache/pain in my upper back area, along with a bad, deep cough (usually i cough up mucus). Does anyone know what could be wrong with me? I don't have a fever.