I'm getting back into shooting/carrying after not doing either regularly for a few years (lived in an extremely anti-gun area for a year and life got in the way when I came to a more gun friendly place). In shaking off the rust, I've noticed that if I try to use anything more than what I'd call moderate pressure with my support hand, I get a shooting pain that seems to originate in the meaty part of the thumb and run to about the last joint. It feels more like nerve pain than a repetitive use injury (I just dealt with tendinitis in my strong hand elbow earlier this year). This happens with dry and live fire, seems to happen regardless of the gun I'm shooting (PX4 CC, G19, or M&P9C).
I searched the forum and found several threads about hand pain, but nothing that sounded like what I'm feeling.
Has anyone had this kind of pain before, or have an idea of how to prevent it?