C.O.
Widower:
Have you thought about going to the doctor to have it examined by a doctor instead of asking random strangers on the internet?
None of us are doctors, and if we were, there is NO WAY any of us would diagnose you over the internet. It's the like girls asking if they are pregnant.
Swelling and pain is your body's way of saying something is wrong with your body. Make an appointment and go get it checked out.
Good luck!