the lord speaks to us on the inside. i do not doubt your story or its importance. i too have had a similar thought about a past death. it seemed much too real to ignore.
trust yourself over anything anyone else says. like me, you have been taught by fundamentalists that reincarnation is not real but a "trick of the devil". such experts on the evil one should switch gears and become experts on godly things instead.
sorry to hear youre not feeling good. i hope for more joy in the life of hopinso!