Congrats on completing 21 days of water fast.
It seems to me that you are still detoxing. Sweating at night and cold feet sounds like adrenal and thyroid issue. Thyroid test will not tell you anything. Do a basal temperature test for three days upon waking and if your temperature is below 96 degrees you have low thyroid. If it is indeed low then start taking Lugol’s Iodine
and co-supplements. There are websites with Adrenal fatigue symptom test questionnaire which you should fill out and see if you have Adrenal Fatigue or not. Dr. Eric Berg has a good website and remedies for that.
Stay on raw plant based diet which should help you heal your issues. Hydration is also very important.