Why every time i eat no matter what my stomach gets inflated and hurts? endoscopy, colonoscopy, liver etc... is fine; what's wrong?

Try probiotics: Adding probiotics can be helpful to improve the "good bacteria" in the gut. Eliminating dairy products and foods that contain gluten for 2 weeks to see if the symptoms resolve can be helpful as well. It is helpful to know all your tests have been negative. Eating a nice variety of cooked veggies and lean protein can help improve your symptoms.

Bloating: I am glad you have had evaluation. Have you looked at the amount of wheat and dairy you consume? Sometimes eliminating these for a short period of time may give you relief. You also may struggle with Irritable Bowel Syndrome.