Questions and observations

Is it normal for one to feel tired and a little foggy in the brain when first starting UT.
Im just a week into it,Injesting 2 to 4 ozs a day. Im a little more run down than usual.Its not a big problem, I was just curious.
My bowel movments are looking alot like when I was on a Colon Cleanse using P&B shakes,Has anyone else had this happen.
Ive also learned clear means chug it down no problem,Yellow means hold the nose and choke it down.