Blake still feels guilty towards Yang from previous events that cause injury and her own power control is not. When Yang would say it doesn't matter, but she still is concerned, it.
Blake also felt wronged Yang from previous events that cause injury and harness the power of her own. When Yang tells her that it's okay, but she was still worried.
Blake still feel sorry for Yang from previous events in injury and to control the power of her own, not. When Yang said it was okay but she still worried.