Your unknown stressor is the result of adaption to stress and is a chronic condition. I have had it for over 20 years and I did make some small improvement but other things have largely prevented healing and will take some improving. I will have a go at it once I have resolved Increased Digestive Permeability aka [incorrectly] Leaky Gut. Every persons digestive system is by it's nature, leaky, it has to be to function and absorb nutrients. It's when the permeability increases above the ideal that adverse effects are experienced. SIBO is usually the result of incorrect stomach function and often hypochlorhydria.
With regard to your adrenals, I have everything that constitutes adrenal fatigue but I would not say I have adrenal fatigue because it is a false idea IMO. TCM gives the correct ideas on what is really happening and how to treat it and Iridology can show how the nervous system and brain changes. The nervous system in the kidney/adrenals mirrors two brain areas and there are changes in both in these conditions and also depression.
Iridology works best with lighter irises ie blue/grey/green but can still be seen in darker irises if you look very closely with good lighting. Blue/grey/green kidney markings can be seen clearly from quite a long distance ie several maybe 4 or 5 arm lengths with good lighting. It shows as a grey marking in the kidney/adrenal areas in both irises. When the nervous system (adapts) degrades the kidney area develops a grey marking which proceeds from the iris rim towards the nerve wreath, 1/3 the way from the pupil normally, where the adrenals are located. Healing this can be done but it depends on other things which is where I have problems.
Supporting the Kidney energy (Qi/chi) is helpful and there are Chinese herbs which can do this. I use Tu Si Zi/Dodder seed which helps reduce the adrenal load, it does also tone the kidney and liver energies which can be seen in the iris as rings which cast shadows in the iris. These also need to be significantly reduces or eliminated to allow healing of the nervous system and brain to produce long term resolution. Emotions come into this as most people do not handle emotions correctly ie they are afraid of expressing certain emotions which causes the changes in the kidney/adrenal zone.
IDP usually compromises digestive function and can lead to some degree of constipation or slowed movement from the extremely high liver detox using up all available choline for phase 2 liver detox processes which can lead to insufficient for acetylcholine production which can also have an effect on memory. Memory issues can be a consequence of all of this. This might also influence your mercury detox problems and so will Glutathione levels which will also be less than ideal.