Questions about pain and being grounded

Hi All!
I've recently started receiving Reiki healing and have been experiencing bouts of pain afterwards. Asked Andreas about it and he said it was cellular memory being released. Seems some trauma from past life (lives?) is being brought up. I haven't been surpressing it with pain pills, but was wondering if there was anything I could do to help assist the release of this stuff. I read below about drinking lots of water and bathing in Epsom Salts , would this help? Do you have to remember the past life/issue b4 you can fully release it? I also get confused, is this from past life, or is this just allergic reaction or some other purely physical reaction? All I know is that after adjusting my diet and doing some cleanses I was feeling better.
Now it seems I'm going backwards into this daily pain. It's very discouraging.
Also, I noticed that Reiki healers are barefoot when they work. I assume this has to do with being grounded. Recently had a dream I posted on Dream Forum, "Staked Tree".(Please read) I believe it's telling me of MY need to be grounded. Can anyone enlighten my about this? How do you ground yourself?
Thank you and Blessings, Marj