Nerve Damage in Epigastric Region.

I had Epigastric Pain radiating to back and constipation for nearly 2 years. I have done Laparoscopic Surgery in December 2024 for release of Celiac Artery Compression in the Epigastric region. I didn't have any pain for 1 month. But after 1 month of surgery, I again started feeling the same severe continuous pain in the Epigastric region and the pain is radiating to the back. The pain becomes severe in back sleeping position. Also again having irregular bowel movements after arrival of this pain. CT scan and Endoscopy taken in February 2025 shows everything is normal. What may be the reason for this pain? Is there possibility of Nerve Damage in the Epigastric Region? Is there any test to find out Nerve Damage?