the way to find out is to ask.... ask for the rest of the dream, see a healer, if you meditate (or even if you don't) there are ways! these are your memories and they are not locked in a vault. if you wish to have help uncovering it, there are healers in every city that can do this. sometimes people who work at metaphysical bookstores will know of someone who can do this. i do know of 2 people that work via phone and can help you if you wish.
having lifted 100+ past life memories in the past 2 1/2 years, i can honestly say that i don't want to know the stories anymore.... i just want the trauma, or the memory (if it is negative) lifted. i am clued in enough these days to where i know when a past life memory has surfaced, and when one does, i either try lifting it myself or getting help from the healer i've worked with. some past life memories are positive and helpful and these have shown up too. they're not all negative.