Is Candida killed by high temperatures? Not in my experience, and I've been sick plenty with Candida.
I think this is a pretty good example of what happens when people get their Amalgams removed improperly. If you're not going to do it right, don't do it at all. Mercury poisoning is no joke and can have repercussions (to the nervous system) that you can't see until 5 years down the road. Dr Huggins is the best, you should at least read his book "It's all in your head" and get his client preparation manual
If you have the rest removed, at least use a rubber dam. I can't believe your other dentist did it without.
I feel really bad for you and I don't know what to advise you now. I'd get expert help, maybe consult with Huggins, consult with other experts on mercury toxicity. For detox, the best non-chemical methods are Far Infrared Sauna s and sitz baths.