There is also a wide variation in the percentage of different rodent species that go on to develop chronic pain after they have been exposed to an acute pain. One can breed these rats and mice so that this same sensitivity to acute and chronic pain passes through the generations. This is proof for a hereditary genetic factor in pain response and pain tolerance. There is no reason to think humans are that much different. We know from experience that some people have a high pain threshold and some people have a low pain threshold.
Some people recover from a painful injury quicker than others.