Dear Healingbird,
The first Reiki 1 class, there was no mention of anything like this. However, the next Reiki 1 class from a different teacher, this concept was stressed . Of note & I find this significant, the group exposed to the teaching of "releases" before hand did have students who experienced symptoms after attunement & with Reiki. This was foreign to me at the time. However, if you tell a group that this is the way it will be, a certain percentage of people will automaticaly comply.
The only time I have had significant symptoms I felt were connected to anything to do with Reiki was during my participation in a healing ceremony when I was Reiki 1. I was too inexperienced to realize that more than Reiki was being utilized. The next day I had a flu like syndrome which my teacher implied was the bad energy pulled from the sick person. Myself, I am of the opinion that I wasnt adequately prepared for this type of healing ceremony & should never have been included with level 3 practitioners & practitioners of other "disciplines". Do I think it was Reiki? No, I dont. There was a great deal of fear in that room as there was a diagnosis that terrified 2 of the people involved. Fear can produce physical symptoms. ( Ever have diarrhea before or after a final exam?)
Go into something will love in your heart & energy field or go in with fear & likely the aftermath will be different, IMHO.
On a day to day basis, we are exposed to numerous living beings and substances that we react to including food, germs & environmental toxins. Alcohol & improperly handled foods, molds, etc. have given me after effects Id prefer to forget!! :)
Always drink lots of water after Reiki.
No, it is not "normal" to have violent after effects after Reiki.
peace & joy,
holobon