If my gallbladder is fine, what else can cause right upper quadrant pain?

Stomach issues. It's very possible that this could be some sort of gastric or duodenal ulcer in the stomach or small intestine. If this persists in spite of otc tx with antacids and / or h2 blocers like Zantac (ranitidine) or ppi like Prilosec then you should see your physician. Common bile duct stones and pancreatitis can also cause symptoms like these as well.