I have a mystery condition and would love to hear

Patient: I have a mystery condition and would love to hear ideas on what could be wrong with me. For reference I am an 18 year old, I am 6 feet tall and 215 pounds. I am extremely active, I have wrestled and played football for the past four years, I am probably considered somewhat overweight, but exercise almost everyday, often twice a day, I can run about a 7 minute mile, and have a resting heart beat around 60 or so. Around two months ago I had a fairly bad case of tonsillitis as I had been having sore throats often for quite awhile, (I need my tonsils removed iv been told) I saw a doctor and it got cleared up rather quickly. About a week later it seemed to be sort of hard to breathe, I kind of just didn’t think about it, until I went to workout and became dizzy and my chest began to hurt, I got very worried and suspected heart issues, and went to the walk in clinic an hour or so later. They did a chest X-ray, and blood work and said I had walking pnuemonia. They gave me an antibiotic and after about two weeks or so I found I was able to exercise again, although my breathing didn’t seem to get better. I also seemed to get random pains that seemed to be underneath my left rib, they come and go and vary in severity, nothing seems to bring them on. One day they seemed so bad I almost went to the ER. I scheduled another appointment and they took another xray and said all fluid was gone from my lungs, (they originally said the fluid was in my right lung by the way.) they took my vitals which were all normal, and scheduled me for an echocardiogram. I got the echo done and they told me everything was normal, that was probably around a month ago or so. It still seems I can’t take a full deep breath without yawning, and find it hard to catch my breath while running, although I still can exercise without pain. I decided to post this because before today I hadn’t noticed my breathing being too much of an issue, and I also began having the pain on my left side again, which I can almost press on and make it hurt worse. I really just want to be able to breathe normally again, it would be awesome if someone had an idea what is wrong, as the last time I spoke with my doctor she basically said she doesn’t know what is wrong with me and told me she could do a ct scan to look for blood clots in my lungs, but doubted it was anything like that. I also don’t have very good insurance so I can’t afford to keep seeing my doctor.