That would contribute to knee problems for sure. As to
fatigue, what is your lifestyle like? Do you eat well, take a multi vitamin, exercise? Those things aid in proper energy. I know that when I have caffeine as part of my day in the form of pop/soda, I'm always tired. I do better without that. What is your sleep pattern at night? Do you have any stress going on? And could you be depressed? Medications that you are taking? All these things could lead to fatigue?