I Have Kidney Stones Which Are Stable And Not Changing

I have kidney stones which are stable and not changing for the past several years. My question is whenever I eat anything that has pork in it I get a bad pain in the upper left side of my neck, almost like a stiff neck. No amount of pain medications helps it. It’s almost as if my body has to process it before pain is relieved. So I am wanting to know what the cause of that is cause there are a lot of foods that I like that I am missing out on due to this issue.