What chelation method or protocol are you using?
I would highly suggest Dr. buttar's method, he uses DMPS and transdermal DMPS and I personally know someone who was cured of cancer from being treated by Dr. buttar (not only chelation but others). My environmental doctor was trained in metal toxicology by Dr. Buttar's program and cured him own son of autism. the idea behind chelation is DO NOT DO TOO MUCH, and TOO FAST. It has to be stable and low doses constantly. It's kind of good to hear that you felt a definite "High" but that crash that happened is most likely due to wrong chelation method. There's a lot of strong opinions on this and the whole Cutler group, and those who believe in natural chelation cilanto, etc. but based on my research, there are very very few doctors among the holistic/integrative medicine doctors (and probably ZERO among conventional MDs) that know how to do it safely.
Also, chelation will flare the yeast and make it worse. I've heard this from parents of autistic children, and many doctors. Everyone's different and if it helps you, great! But just be cautious of that fact.