Most common cause is any injury.
If not you might be having some form of arthritis for which you have to visit an orthopaedician for examination and proper diagnosis.
X-ray will throw some light and if required other tests will be performed.
You can also have these symptoms like numbness in both hands, left palm burning, right middle finger pain with back / spine problems.
Take an appointment near an orthopaedician.
Take care!
I am experiencing numbness in both hands, left palm burning, right middle finger pain
Go, for a simple X-ray of the finger. If you have a fracture you have to wear a splint.
If it is only pain and inflammation, rest and anti inflammatory drugs will do wonders.
Take care!