Hello dmattwads
If I get cold (e.g. in a cold wind or getting out of a warm bath into a cold bathroom) the next day I’m always very tired. It took me years to realise because the cause of the fatigue and the onset of it are separated by so many hours. Perhaps you are the same? As far as I know it is because of low qi, which I think is in turn caused by a blockage in the flow of qi although I don’t know where the blockage would be physically situated.
Best wishes
Jo
