Yes I did
As long as you don't have any underlying medical conditions like diabetes, then you should be alright doing it. But it is always best done supervised, or if not in the least getting checked up and easing into the process over a period of months/years (depending on the person), like for example starting by removing heavy metals from your body and then increasing the fast periods incrementally.
In the situation described by you, your body most likely did not enter into a full detox/ketosis mode because you still had some nutrients and sugars despite being on very little food. With a water fast your body enters into a level of complete healing, but it is best done during time away from any work, whereby you can be in a mode of complete rest. It is sort of like the same process animals naturally go into when they are injured, they find a secluded place without eating anything until they are either healed or die.
I do agree with you however, that it is not a process for the faint hearted or weak. Most people could not even conceive doing it, and to be honest I would not recommend it, simply because of the likelihood of them panicking or doing something very wrong due to lack of proper preparation and research.