How do I get rid of the smell of stagnant water?

You should have contacted your insurance company over this accident. A professional carpet cleaning company who also performs water restoration would have dried the floor, the walls, and under the cabinets, using special tools and equipment, air movers and dehumidifiers. Sheet rock will wick water up and hold it for days. You may have mold issues, as it takes 3 days for there activity to start, humidity and temperature work together in there favor.