You Ph is very low. Do you have reagent paper at home? try to test it during the day, say, 4 times.
with such low Ph, did the doc run kidney tests?
You have low blood pressure, cold intolerance (could also be heat intolerance when it around 30C), probably you also getting dizzy when get up fast, mild depression. These are symptoms of low thyroid function.
Coated tongue - intestinal putrefaction according to TCM. It could be SIBO in our med terms. I had it pretty white myself. This also was the last thing I gotten rid of though it should be the first thing.
I would suggest you get rid of the "white tongue". This improves digestion, cleans you guts, restore flora. You will be able to digest and absorb!!! nutritions better.
Check under my name. I have posted how to do cleansing with castor oil. Do it once a week until white coating disappears from your tongue. Your digestion will improve, you will feel more energetic. Especially, the first time or two times.
Ask the doc to run complete thyroid profile or at least TSH, FT3, FT4. Check at DrRind.Com. Dr. Rind explains it very well. In my case, it was conversion problem. Hi normal FT4 below average Ft3 slightly high TSH. Ideally, TSH is 1.3 - 1.8 (Dr. Rind).