This sounds pretty fanciful and ungrounded. In general doctors don't "consider chronic pain kind of not a thing". I have chronic pain, I see doctors about it, and none have ever expressed any doubt. Quite the opposite: some of the doctors are chronic pain specialists. There are pain management centres at hospitals to help people with it, and they prescribe "powerful painkillers" if they're useful, but they often just aren't (e.g. for me).