Yes, that's exactly right. EFT can really get things moving---faster than the body can handle without cautioning to go slowly and safely.
I'd try a phrase like 'my body may not realize that it needs to keep removing the cadmium at a slower less painful rate that doesn't accumulate so much of it in my kidneys at once'.
Cadmium buildup is the reason Dr. Clark found for high blood pressure, so proof it was working, eh?
And welcome to the brave new frontier of energy healing. It's new territory for many, and has it's share of bears and Indians--we're writing the map with cautions now. :)