Predicting bottom of current selloff?

Just trying to predict the bottom of our current bearish selloff from midday today. I believe we formed a head and shoulders from 05/27-06/09, the breakdown happened mid day and I believe SPY could continue to fall a little farther to $399 tomorrow morning.

I believe either one of two things happens then, either we bounce and retrace to 416.27/420.15, or we end up breaking the $399 level and begin a descent towards our 380.55 support level (our previous bottom).
If we do end up falling to the 380.55 level I'll re-evaluate the chart, but I believe we would bounce and form a double bottom causing a bull rally. (very speculative at this point)

Just my point of view, take it for what it's worth.