Sounds like CFS. Check out the symptoms. Dr Myhills site has a lot of information which might prove useful.
A thickly coated tongue is common for any yin excess disease which Chronic-Fatigue-Syndrome is very much so. Altered digestive flora is common in CFS, due to poor stomach digestion. High ammonia causing the muscle weakness, fatigue, brain fog, often a shifted body clock, awake at night and sleeping late. Your body is under considerable stress, your immune function is compromised due to IIPS (Leaky Gut) this is affecting your nervous system function drawing your Qi away from the outside of your body which is affecting your blood pressure and hair loss. This usually shows a thick scurf rim around the outside of the iris, which I would expect in your case, indicating poor skin function, low blood pressure, possible hair loss in extreme cases and poor immunity near the outside of the body.
Your hypothalamus function could be affected and so could your pituitary gland in extreme cases such as myself.
Thyroid function tests are useless when there is hypothalamus dysfunction because they usually show as normal even though they are not.
Frequent urination? Lots of mucus, saliva etc?
It would be helpful to do everything to make digesting food quicker. It might be worth trying consuming liquefied food by using a blender and drink quickly. Don't drink too much fluid after because it will weaken the low stomach acid levels and delay digestion. DO NOT EAT OR DRINK for at least 3 hours following food. Digestion could take many hours. Eating small portions might be helpful. There is often more tiredness following meals due to increased ammonia produced by the digestive system. Urination tends to increase because of it in an effort to eliminate it.
You could get some amino acids to help lower ammonia such as Ornithine Ketoglutarate and Arginine Alpha Keto Gluturate AAKG. Ketoglutarate/Ketoglutaric Acid helps with energy production and ammonia reduction and is present in both these supplements. Ornithine is longer acting and Arginine gives boost to blood levels of arginine and the ketoglutarate should be helpful. Some people use Citrulline malate but I have not found it to be helpful. I do take malic acid which can be helpful so the malic acid salt in citrulline does not provide anything extra for me.
High dose B12 in methylcobalamin helped me quite a lot. I take 25mg/day which loads my blood stream and B12 is off the scale. This helps lower ammonia, lower IgE antibodies and can normalize the body clock. Mine is much more normal now. Find a cheap source if you can. It's not a cure but it can be helpful as you are probably low in B12 anyway due to poor digestion because stomach acid is needed to absorb B12 in food. I have been thinking of importing a powdered form but I need to investigate import duties and fees etc.