Pain in Palm While Pressing

I have an unusual pain that develops in my right hand only while overhead pressing. It can carry over into bench press too once it’s aggravated. No problem at all during pulling/grip movements.
I would love to know what this is called (can’t find it online) or if anyone else has it, what works to relieve/cure it?
The pain seems to be along the tendon leading either to my pinkie or ring finger, but its in the bottom half of the palm toward the wrist.

When it happens I typically try to open those two fingers, which doesn’t make it go away but makes it tolerable; but the pain breaks my concentration and I can’t focus well enough to successfully complete my pressing sets.