Hi, There are so many other reasons for fatigue with hot flashes other than thyroid problems, goiter is just enlarged thyroid gland and can be functioning absolutely normal. Consult your Doctor for proper and detailed clinical evaluation, physical examination to think about probable cause. If you are a female in premenopausal years then hormonal imbalance can be the commonest cause. Other causes should be ruled out by appropriate tests of blood and treated accordingly. Till then watch for your anxiety levels, stress and should also be controlled. And have symptomatic treatment till then. Take care. Hope I have answered your question. Let me know if I can assist you further. Regards, Dr. T. Chandrakant, General Surgeon