Here is very simple logic, S&P future do not drop 50+ points consecutively. People who are hitting bids relentlessly are big stake holders, they want out so trend so far is down.
I do not think its a normal 10% variety correction. Stay short till your system say, it is fast market so stay nimble, 10 20 points drop or gain will be in minutes, use stops.
I tried to go long near the end on Friday but stopped out with loss.
I am still short.