I would eliminate all gluten and dairy products for a week and see how you feel. Gluten is found in wheat, rye, oats and barley. I find gluten gives me major brain for and increases my depressive symptoms. Dairy is not great for any sinus or GERD issue. Just observe how you feel, or better yet, track your symptoms in a journal where you also record your food intake and see if you can detect any correlation. Also, testing negatively for food sensitivities doesn't mean a whole lot, as you can still have all the symptoms.