i can relate to the jubilant/despondent experience and sensation. it's almost like my body is fighting with itself to choose which one it wants, then i'm suck with a mix of both or a spurt of energy and then a spurt of exhaustion....frustrating and also just very strange!!!
otherwise, does sound like perhaps some dissociation? probably worth mentioning to doc, can't imagine it would hurt. hope this clears up or becomes less frequent.