Vintage Willow skirt, long, black/white tweed size M?

Love this skirt! No tags to tell me size, but I’m guessing a M (see measurements). No tags for fabric content, but feels like a cotton blend (heavier on the cotton) Straight, pencil style with cute buttons embellishing the back . Elastic waist. In excellent pre loved condition! 15 inches across waist 32 inches length