I can no longer bend my double jointed thumb without excrutiating pain, not even to open doors, because of crocheting… which relaxes me?
Looks up… “This is not funny! Oh ok, maybe just a little… OK, OK! Maybe a lot!” sigh… this kind of shit can only happen to me. LOL

I guess I would work on it,
moisture, heat, rub in some ointment,
stretch the hand, massage the forearm, etc?
Once you take David’s advice, then work on strengthening. This can be done with a soft spongy ball and light squeezing exercises…this can be done at work or at home. Also, they have at medical supply places are thumb isolators for the very sore days when doing anything can agrivate the involved joint(s). Icing is also recommended for the first week, then heat.