Is this chronic fatigue @Scream58? I had a complete physical breakdown several decades ago and had to expend my energy reserves for the laborious task of breathing. It was horrific. Took me many years to level out and I still exhaust from excessive stress. To be honest, I can even exhaust from extended periods of happiness or having to make big decisions. It's all tied into emotions which were severely overwrought from stress prior to my collapse.
Having to travel for 3 hours for a doctor's appointment must be dreadful. I fully understand how you have to build up your reserves of energy in preparation and then afterwards in recovery. I hope your consultation goes well. Certainly a day out, isn't it?