Of course we do not diagnose on line and accurate diagnoses requires and exam.
But, given the history this is most likely tendon irritation. Tendonitis, or tendon strain.
Exam is needed by an orthopedist preferably.
Bone inflammation from some cause [unlikely]
Ligament strain in the joints [not so likely].
The standard medical procedure until seeing a doctor would be ice, then heat, ibuprofen and resting the hand.
OK, let me know if you have further questions.
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