The fact that it feels really weak is a good clue.
Something else to consider. When I showed up with shatterred little finger metatarsals in both hands (not a climbing injury, just pulling stupid hard on something,) the hand specialist explained to me that this type of injury is almost unique to climbers. We learn to over-ride our “tendon sensor reflex.”
He explained that a normal person pulling on something will reflexively let go when tendons or bones near their breaking point. Climbers, on the other hand, learn to push past this reflex to avoid falling. Apparently fear of falling trumps risk of hand injury. And my experience indicates that once we learn to push past the safety margin in hand strength when climbing, we will do the same in day to day life as I did.
Also, I think that other body parts are subject to injury when climbing for the same reason, that is the desire to not fall off. Shoulders and elbows come to mind.
Regarding the fingers and forearms, Google "golgi tendon organs" for more info...