A few thoughts for you--sorry no time for a full reply
Tuna is high mercury Hg fish!
High sulfur/thiol foods and supplements will kick up Hg. Some of the kicked up Hg will be removed from the body. Unfortunately some of it that was in parts of the body not so vulnerable to Hg will find parts of the body that are quite vulnerable and that hold on quite tightly.
Frequent urination and endocrine problems--temperature regulation, etc--are symptoms of Hg. However, when a person has an Hg problem I expect to see at least one mood related problem, especially reduced stress tolerance, maybe to the point of anxiety and some depression.