I don't get it.
What's the benefit of fasting to "detox" unless you're eating like crap to begin with? Depriving your system of vitamins and nutrients for days at a time
helps you? Sorry, not buyin' it.
"I'm not eating food, just drinking tea"... that seems a bit silly. You're getting your energy from caffeine instead of carbs and protein? How can that be a good thing?
"I get euphoric/hyper-alert after X day"... well no kidding, you can get high as a kite by depriving yourself of sleep for days at a time, too. Or even just by drinking wayyyy too much water. It's because your brain chemistry is all messed up. Your body is in survival mode and trying desperately to stay alive, but not functioning properly. It's not a religious experience and it isn't good for you, you're just abusing yourself.
You can get just as euphoric and lose plenty of weight by snorting meth, but no one claims that's a "cleansing ritual".
Regardless, as someone else said, talk to a medical professional before you attempt anything radical. Who knows if you're an undiagnosed diabetic or something and might get really sick messing with yourself this way?