Thanks for all the additional details. Having gone through your further descriptions, I feel that we might be dealing with costochondritis, and maybe Tietze Syndrome, as we have some associated swelling as well.
Usually it is a problem of a short duration, but can be prolonged to several months in some cases. NSAIDs like Advil/ Motrin/ Aleve usually help, but rest is as important and we must not perform activities which might aggravate the pain. Hence you must stop any exercise which brings on this pain or aggravates it. Heating pads are also known to be of some help. Some patients do keep checking frequently if the pain is gone, and that should be avoided, and avoid lifting heavy objects with your arm of the affected side. Given some more time, I think this pain and swelling will settle down.
That said, if the condition gets aggravated or does not ease away say within a week or so, please do get yourself checked up again, so that an appropriate management is instituted, and that we do not miss out any serious conditions.
I hope that this information helps answer your query. Please feel free to inquire if you have any remaining concerns/ doubts, as it shall be a privilege and a pleasure to try and help as much as I can.