Thanks for your query.
The symptoms you describe occur more commonly after a spinal anesthesia
, less commonly after epidural.
Please check if a combined spinal epidural anesthesia was given.
In any case, please try lying down without a pillow or any head elevation.
Consume plenty of fluids, atleast 4 - 5 litres per day.
Try local heat and gentle massage
IF the headache and stiff neck
doesnt subside, consult your doctor for painkillers and probably the opinon of the anesthetist also.