Signs of a short term fulcrum top has been evolving since Friday's 10 h EST, in the chart the basic explanation is given; I add that although a confirmation pays off, the best risk reward is done by speculation, remember to include Opportunity Costs, if wrong now time is the main affected in throughput (increasing costs and inventory).
To leave the trade SL at the high, objective 18130 first, then see if there is a high buying or the bulls are vulnerable at this moment, therefore more downside is under way.