hi thank you for your query. thank you for the detailed history the possible causes for your pain can be- 1.Pancreatitis- Inflammation of the pancreas which gives severe pain in the epigastric region along with nausea and tenderness. 2.Gallstone-A small, hard crystalline mass formed abnormally in the gallbladder or bile ducts from bile pigments, cholesterol, and calcium salts. gallstones can cause severe pain and blockage of the bile duct 3.Ulcer-a gastric or a duodenal ulcer can also cause pain and tenderness. i would advise you to book a consultation with your GP,and i would also recommend you to get an ultrasound done along with complete blood picture done.it ll determine the exact cause and we can start the specific treatment thank you, wishing you good health