In 2008 we had very similar case. S&P500 tagged twice (double bottom) at the weekly 200MA. That lead to a furious rally towards the weekly 50MA. What happened after that... Well you all know.
Repeat after me :"This is not 2008, This is not 2008, This is not 2008, This is not 2008, ...."

I recommend looking the related idea also.
sp500indexs&p500shortSPX (S&P 500 Index)S&P 500 (SPX500)SPDR S&P 500 ETF (SPY)

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