What would cause pain in my lower right side of stomach area when eating & drinking?

Many possibilities!: First, the "stomach area" means different locations to different people. So, we divide the abdomen (tummy) into 4 quadrants (quarters). The left upper has the stomach and some intestine, and can hurt from gastritis, ulcers, reflux, etc. The right upper has the liver and gall bladder, which hurt when there are gallstones or sludge. The right lower has the appendix (hurts in appendicitis). Etc...