Why do I get lower left abdominal pain after meals?

Hello doctor,

I have been experiencing abdominal pain for the past one and a half months. The pain usually starts after meals, especially after lunch or dinner, and lasts for about one to four hours. It occurs in episodes, gradually increases in intensity, and then subsides on its own. The pain is mainly located in the lower left side of the abdomen, near the navel.

I consulted a doctor at a local hospital, who noted tenderness in the colon and suspected an infection. My Widal test was mildly positive (report attached). Based on this, I was admitted to the hospital for five days and was treated with antibiotics and laxatives, but there was no significant improvement.

I have undergone several investigations, including endoscopy, colonoscopy, X-ray, ultrasound, urine test, and stool test, and all reports were normal (attached). I was prescribed Mebiz SR (Mebeverine) and O2 tablets (Ofloxacin and Ornidazole)twice daily, and Ultracet (Tramadol / Acetaminophen) and Hyocimax (Hyoscyamine sulphate)tablets as needed, but I did not experience relief even after completing the course.

Previously, I was also prescribed Smuth suspension (Sodium picosulphate, Magnesium hydroxide and liquid paraffin), Rifaximin, Dolonex DT (Piroxicam) 20 mg, and Perinorm (Metoclopramide), but none of these medications improved my symptoms.

There is no prior history of similar complaints. The pain began about two months ago and typically starts suddenly after eating.

1. Could there be another possible cause for this persistent abdominal pain?
2. What further tests or treatment would you recommend?

Please help.