SPY is at horizontal support and is peeking below the 100-day sma. The previous two selloffs didn't make it much further than 1.5% below the 100-sma, as shown by the 1.5% envelope band below the sma. This suggests a buying opportunity may be upon us within the next 5 or so trading days, judging by previous price action. I wouldn't want to hold long over the weekend so I will wait for next week to see if a bottom is formed on the hourly and shorter time frames. We'll likely reach the envelope line this week and see a bounce next week, according to this analysis. I have no position, but will keep this analysis in mind for day trading.
We could be forming a major top, but I don't think it will sell off from here, it needs to flatten out more before selling off much further than this, in all likelihood.