You really need a primary doctor. Your surgeon and GI only focus on their areas of practice. ER departments focus on emergencies.
My back pain started a decade post op. I could not take ibuprofen anymore due to liver inflammation. My primary referred me to a rheumatologist. That was when I was diagnosed with IBD related (enteropathic) arthritis. All my labs and imaging were negative. Certainly, the fact that you have abdominal symptoms in addition complicates things. But, you need doctors of different areas of expertise, and the PCP can refer. He can also prescribe appropriate pain medication in the interim.
I hope you get some answers soon.