Read and understood that you have undiagnosed pain on the left upper abdomen for the last 6 years. just below the lowest rib.
Your mentioning the details about the history related to increasing factors, relieving factors, bloating, bowel habit and all would have helped me more to tell you the diagnosis and obviously the treatment.
Nor have you posted any reports of previous investigations. Anyways, with a short history this looks to be a pain of costochondritis.
Local tenderness will prove this.
Treatment with anti-inflammatory medicines and oral steroids if needed.
If there are symptoms associated with bowel, further investigations of enteroclysis, colonoscopy and so on would be necessary before a proper treatment be started.
Hope this helps.
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