S&P 500 rally getting tired?

Updated
Context: My bias is that we are in a counter trend rally that is reaching its conclusion. We have been bumping up against a trendline coming off the bottoms of lows at the end of March and beginning of April. We have also been trading in a channel with that trendline as top of the channel for about a week. Breaking the channel to the downside will put the market in the position of possibly testing support in the 2858 to 2850 range. Breaking that support would look like a confirmation to me of the end of this counter trend rally.
Note
I should say that using the 2850 area to get flat if you are long would be a conservative move, getting short there would be more aggressive. If you are less of a trader and more of a long-term trend follower a violation of the 2630 area would be a more conservative area to consider short positions.
Trend Analysis

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