The differences in the body language of mental anguish and physical pain may be subtle. This is where memorizing the body language of our loved ones is vital. We won't always be right, but if we know our loved one's movements and expressions well, we should be able to know when medical intervention is called for. This knowledge will also help the treating physician, if we are fortunate enough to have one who listens.
With Dad, even though his pain was obvious, there was an attitude by some medical people of just giving up or giving in, as if they'd done all they could. That was unacceptable to me. I knew him well. I could generally tell if physical pain was his major problem, or if his demented brain was the problem. I pushed and complained. I made noise. Eventually, the culprit was discovered and some of Dad's misery was halted.
We are the advocates. We sometimes need to push to make sure everything that can be done, is being done. That often means knowing the language of our loved one's body and doing our imperfect best to help him or her when we can. If there is nothing we can do medically, we can hold on tight, offering the comfort of love through touch. It's something.