Girls Aloud singer Sarah nailed her back somersault on the trampoline .
Girls Aloud singer Sarah was thrilled -- but was visibly upset by her score , which was lower than her 28.5 score last week .
Girls Aloud singer Sarah nailed her back somersault on the trampoline and was thrilled -- but was visibly upset by her score , which was lower than her 28.5 score last week .