Another thing you can try is to do this fast as you are until you are tired of it (hopefully more than 21 days)and then alternate with one week on food and one week on a full urine and water only fast because it will be much easier then. Keep alternating until all your symptoms have gone.
If we can believe others who have written books like John Armstrong - The Water of Life, then all your symptoms should disappear if you fast for long enough.
I am 61yrs, westerner, and I fasted on urine and water only last October for 20 days and I feel much better now 4mths later than I had in the same time after my previous fasts that I did each year of 10 days, 13 days & 14 days.
My blood pressure is not increasing again like it used to do after each fast.