NASDAQ currently has call walls above at 3850 and 4090, put walls at 3700, with key resistance at 4000 and 4090 (all-time highs) and key support at 3700, based on options-market positioning.

Apple and Amazon earnings this week are critical because they are mega-cap tech holdings that dominate the index; a weak report could trigger a 'fast flush down' to 4400 and 4350 support levels.

If the S&P 500 breaks below the 4500 level and closes below it, a fast flush to 4400 is likely, with potential support around 4350 and 4300 if the correction runs deeper (similar to February and December corrections of 300+ points).

Tech sector is very overextended with multiples at elevated levels relative to historical averages; smaller caps (Russell) are preferable to the NASDAQ, and significant downside correction (5-10%) is likely before meaningful upside is seen.