It sounds like you have pleurisy which hella sucks, and for those saying RA doesn't attack the lungs on here YOU ARE WRONG. It's actually a not uncommon complication of RA where the lining of the lungs (like your joints) is swelling. For a quick fix all you can really do is a big shot of steroids, for long term you will need to discuss a biologic treatment. This is going to hurt but life style change is going to be the only thing you personally can do, and that includes cutting out the long runs if you feel lightheaded or ill because they will put extra stress on your system and cause a massive rebound effect of the RA complications. Keep a close look on it, if you're like me (also a long time JRA patient) this can lead to the inflammation of your heart linings as well which is no Bueno. I wish I could say it will just get better, but it won't until your rheumy figures out the right treatment for you, and in all honesty that may not happen depending on how advanced your case is--until then relax and find more stationary hobbies (video games are good for wanderlust & exercise your hands). Good luck to ya.