Dear-thanks for using our service . I read your question in detail and will help you with my advise. Your stomach pain could be secondary to gas which can move in the abdominal area and to the back. You should avoid vegetables like broccoli,cauliflower and lettuce. Also carbohidrated drinks and alcohol. You can try digestive enzymes or probiotic supplements to help the intestinal movements.Other possibility is irritable bowel movement for which you may need to try medication that helps to control intestinal spasm. Avoid spicy food too.If after doing this diet modification, you still with same symptoms, you might need an upper and lower endoscopy for better visualization of your digestive tract. I hope that my advise has been helpful Dr.Sara