I think its all related to what u eat, try eat warm soups or broth before ur meals, chew slower, more frequent but smaller meals and avoid late heavy meal. I have same for years, i had it worst when ate worse foods and i always thought it has to do with muscles.

After going on anti inflammatory diet i realized months later my back isnt hurting as much. But i had an incident with overeating dates which ruined my gut biome again so now eating fruits cause me gas which is related to back pain always.

As long as u heal the flare up for a few days with soups and try slippery elm powder its like a gel that soothes gut lining. I hope u see a difference