I remember that whole "the market climbs a wall of worry" thing from way back when I was trading tech/biotech stocks in the 1990s. There was never any real reason to worry until "irrational exuberance" set in (Thank you, Alan Greenspan) and people would throw gold at a dog turd, hoping it would turn into more gold.
I'm not actually a trader, so I don't much look at this stuff, anyway... except from a "pop popcorn and watch" perspective. I prefer to back out... WAAAAY OUT and take stock from there.