The December 2018 lows were a test of the bull market. Those will likely break, because we are no longer in a bull market. We are in a bear market.
The 2015-16 consolidation is a likely point for the stock market to regain some stability or if panic occurs, then a lower level will come quickly.
The double tops of 2000 and 2007 are becoming more likely as the stock market decline has become less orderly this week.