Does anyone know what's wrong with me?

Nausea, diarrhea, and digestive problems happen if you don't have enough of the B-vitamins. google for more info. You might want to take a vitamin B-complex supplement (it's like a multivitamin, but only has the B-vitamins in them, like vitamin B12, vitamin B6, vitamin B5, etc..). Make sure you're eating healthy, including foods with the B-vitamins - such as red meat, organic calf liver, tuna, spirulina, chlorella, etc...(spirulina and chlorella are superfoods that you can buy at health food stores. superfoods are foods or herbs that are very nutrient-dense!!)