doubled spell

when cast you feel power in you grow and on your next turn you cast a spell the spell happens twice you can target 2 different creatures if by your next turn you don't cast a spell the effect wears of and you waste a spell slot e.g fire ball happens twice or if its not an attack spell you target 2 different creatures
every level past 5th your able to hold onto the effect for another turn (cant be stacked un less your dm allows it)