Hi and thanks for this query.
I am so sorry to hear about your finger and the pains.
Your signs and symptoms are suggestive of an inflammatory reaction. Because this is at the level of your joints,
arthritis is high on the list. This is probably due to over use arthritis but it could also be due to an infection or other causes.
Yes, it is possible to have arthritis in only one finger.
My suggestion is to start with some pain killers. If the problem gets worse or persist further, then you should try and see your
primary care doctor for more evaluation and treatment. Also, if it is possible not to over use this finger, then please do so.
I hope this helps, provides answers to your worries and guidance on the way forward. Feel free to come back with more questions.
I wish you a rapid recovery.
Dr. Ditah, MD.