Pain is not one substance. There is the steady background kind you can talk over, the spike that stops a sentence halfway through, and the dull ache that is worst around five o'clock for reasons nobody can explain.
Telling them apart changes things. Partly because the description you give a doctor gets more accurate, and partly because naming which one is actually present tends to shrink it. A spike is a spike, not the beginning of everything getting worse.
Release is not always the same as gone. Sometimes it is the distance between pain and pain plus dread.