You could at least start with cleansing your liver, it is inexpensive. My brainfog and aches and pains went away with flushing and improved diet. That does not mean it works for everybody but a clean liver is good for general health and helps with digestion.
I noticed you already did parasite cleansing and the liverflush will help with that too.
You can check the liverflush forum and also Dr.Sutter's forum.
It is always good to start with things which are inexpensive in the meantime you can save for your teeth.
Keep reading the forums and especially the FAQ plus the R posts at the top of every forum to get more information.
Mercury removal and crown replacements cost more like several thousand dollars, so most people try first to solve their problems in other ways, but if that does not work you might not have a choice. I had some teeth done and they were $300 each and the crowns more like $1200, which I have not done so far.