This quick short trade is in line with our bearish view for the S&P500.
It seems that the S&P500 has finished an abc correction to the upside on the 15-minute chart, where wave c is an Ending Diagonal.
If this count is correct then the S&P 500 will start declining in Primary wave (C) to finish the correction started in May 2015; that will lead to new lows during next year.
If you are looking for a safer trade with higher risk/reward ratio then you can trade sex short with your stop loss above the highest price of wave (B) (almost 2115 or 211.7 on spy) and looking to take profits around 1800.
As we always say wave C are "most probably" the fastest, easiest and least risky waves to ride.
Happy trading :)