Hello,
Thanks for posting your query.
It seems that you might be having a chest wall infection either of the rib bones ( costochondritis ) or soft tissues ( abscess ) .
However in order to guide you appropriately it would be kind of you to provide few more details as , the onset duration and progress of your pain and swelling , Any history of injury ?Wether any investigation done or medications you are taking ? Etc
As of now if you have just noticed a sore lump in your rib bone then it could be a costochondritis and which can resolve with analgesics and anti inflammatory medicines ( acetaminophen , ibuprofen etc)
It's best to get it examined by your doctor to confirm the diagnosis( by tests like X-ray chest etc) rule out any infection so that appropriate treatment can be started . It's not advisable to neglect your symptoms as it may worsen with time .
Hope this information helps you .
Please let me know if you have any further doubts .
Awaiting your response ,
Regards

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