Hi,
Headache in an elderly person on the move in a car, driving and getting fainted very briefly, rested in a motel but still weak, blood tests being normal.
My most probable thought would be
hypertension with exhaustion, may be viral infection that has no
fever but gives lots of weakness. The blood tests would be normal.
I would advise you the following in such a situation:
Take further rest if you are alone, do not drive.
Call for help from family or friends.
Try to see a Doctor in nearby clinic or ER for physical check up and take prescription based medicines.
I hope this should help you so that you can reach home safely.
Hope I have answered your query. Let me know if I can assist you further.
Regards,
Dr. T. Chandrakant, General Surgeon