Elliot theory says on a 12345 wave uptrend, wave 2 pull back can not go lower than the high of wave 1 (which is 485). If you look at QQQ today, it bounce at exactly 485 after initial sell-off.
Anyway, if QQQ "closes" below 485, I will need to spend more time to study this. it basically says we are not in wave 12345 yet, and could have deeper pullback.