This pain

This pain begins like a small movement in my belly. I barely notice. Then the feeling grows, and bits of it get stuck around a bone, pull insistently, make me notice. Grows some more, and then I have a hard time concentrating on what I'm doing, have to stop and take a breath. Then it grows again, and I know that I'm in for a bad couple of hours or so. It makes a run for it, enlarges into a wall, until I have to get up from my chair and take the pain and the body it inhabits for an endless walk. There is no sitting or lying down with this beast, this Thing, this mountain of lava. It will eat me unless I go inside myself and ride with it until it's seen the light of day. I must endure it, as the drug has failed. I have only myself to use against the biting, rasping saw of it.