When Macy’s, a store closely associated with Christmas, says there's trouble brewing ahead of the holidays, it's enough to send the world of shopping into a tailspin. The retailer of “Miracle on 34th Street” warned Wednesday that its stores were awash with merchandise after a sluggish fall season and that slow business would force it to go all-out on discounts during the holidays. Macy’s shares plunged about 14 percent, dragging other retailers down, too. The Hudson’s Bay Company, which owns Saks Fifth Avenue and Lord & Taylor, fell 5 percent, as did Kohl’s. Burlington Stores fell about 7 percent.