Maybe you
do have a twin. Separated (at birth) twins often have the same habits, gestures, interests - even though they haven't been together, ever.
Maybe it's a relation. Maybe your dad or mom had a tryst. You could walk up to the guy! Say hi I have an issue of mistaken identity with you - weird huh.
As long as it's not same you - that would be more of a mothman or multiple personality thing
