Sharp chest pain with breathing deeply, coughing or exerting myself, could I have pleurisy?

Question

About a month ago I had what I thought was just a bad cold. Eventually all the symptoms went away except a lingering cough I couldn't seem to shake. Then, three weeks ago I starting having sharp, stabbing pains in my left shoulder blade area. I train Jiu Jitsu and around the same time I messed up my shoulder in practice and so I ignored the pain thinking it was related. But it got worse and moved to the front of my chest, around bra line level. It feels like I'm breathing in glass, and any cough, sneeze, or physical exertion leads to piercing rib/chest pain. When this happens I feel like I can't breathe and start coughing uncontrollably, especially at night. The only thing that helps somewhat is keeping pressure where the pain is. The doctor decided I pulled a muscle in my chest and so far I've been 3 days on ciclobenzaprine and 2 weeks taking ibuprofene every 6 hours. Today I went to the doctor because I'm still in pain, she just gave me a prescription for 5 days of prednisone without any questions or exams and rushed me out the door. My chest x-ray apparently looks normal but, she hasn't even listened to my breathing once and I'm worried it's pleurisy. I'm also concerned about taking an immunosuppressant drug if what I have is caused by a lingering chest infection or virus. The doctor seems 100% focused on the jiu jitsu injury and seems unconcerned about my previous cough, but that injury was to my shoulder joint not my chest area. Any advice? Do I have reason to be concerned about starting the prednisone?

(Also worth mentioning, I'm 3 months into a 4 month trip to Brazil and therefore dealing with the Brazilian health care system)