Pain in ribs and back

I am a 22 year old male, and I have been having dull aches under my rib cage and in my back for over 6 months now. I recently went to see my physician, and he ordered a chest x-ray, which came up clear. Before this, I had been coughing up a thick brown mucus and found a trace of blood a couple of times. That was about 5 months ago, and has lessened or stopped completely. The pain is constant though and is really starting to worry me. I experience this pain very irregularly. Sometimes I get it when I breath in or out, but sometimes not, and sometimes I get it when I move a certain way, but not always. I feel it mostly on my left side, but also on my right side to a lesser extent. Again, it feels like it just beneath my rib cage. What could this possibly be, and what other action should I take now that I've had a chest x-ray?
I don't have health insurance, so I want to know what course of action to take before I go back to the doctors office.
Your help is greatly appreciated

[National Jewish]

This pain could be unrelated to the cough and thick brown mucous.  Since your chest x-ray is clear, the pain could be pleurisy.  In the early stages of pleurisy, the chest x-ray may not show any abnormalities.  This however is unlikely, with a pain of 6 months duration.

I would wonder if the pain is musculoskeletal or related to some type of neuritis, possibly pinched nerves.  It would be important to note if you engage in any regular activity that could put repeated stress on your chest.  This pain may also be related to some type of neuritis, possibly pinched nerves.

I note that you don't have insurance but recommend that you get a second opinion, possibly low cost at a hospital or neighborhood clinic.

[luluair]

I have the same symptoms w/ thick brown mucus and very hard to get up. Sometimes it gets caught in my throat. I had a pulmonary test done a few weeks ago and will get the results on the 16th of march. So i'll let you know. I also have pain in my lungs. Mainly the right. Do you smoke?
Thats why i think my brown mucus is from. Why its so thick i don't know. I'll post later. Good luck.