Finger gone wrong.
Despite being an old bloke, I was blessed with still being quite dexterous. I touch type and work on watches, the latter with zero tremor. However, the joint in the 5th finger of my right hand looked (slight blueness ) and felt wrong recently, and to my horror sometimes would sort of lock over-centre and have to be straightened with my left hand. There is slight discomfort but no real pain.
Just thought I'd ask on here as this is so odd. I just don't recall doing anything to stress it. I've booked to see the doctor, but facing eye surgery don't really want to go to into their waiting room as infection of any sort would mean me losing my place. I'll probably cancel just in case.
As an aside, I'm having retinal surgery in a chair while awake. Vitrectomy and peel, patch and eff-off. How bizarre is that? It's the peeling bit that gives me the scringe.