Why was i asked to keep a urination diary? it is humiliating.

Not if it cures you: Urination diary is important to make sure that the fluid balance between input and output is stable i.e. Intake equals output. If you drink 1.5 liters and urinate only 1 liter on routine basis then you will need to increase the water pill to make it even or else you will get severe swelling and heart failure. You need to keep intake no more than your output to avoid this problem i.e.Restrict fluid.