Everytime i eat a full meal i throw up or have gas. what could cause this?

Peptic Ulcer Disease: This could be an ulcer, reflux disease, or even your gallbladder acting up. Try Tums (calcium carbonate) and go see your doctor if it does not help.

GASTRITIS: You probably have irregular eating habit. When your stomach is empty, gas is accumulated, there is hyperacidity and when you eat a full meal, there is vomiting and gas.