As long as your plants aren't wilting they should be fine it might just take
longer based on genetics/conditions. I've had some WW take up to 20
days to be ready. Once the root bumps start appearing things really
take off and it's only a couple of days from there before they'll be ready.
One thing I noticed that helped speed my times was taking very thin
slices off the bottom 1" of the root tips. This will also help stimulate root
development along the cut and give you a heavier root start.
Also, I'm not sure your cloning experience but I found anything more than
simple RO water and a powder/gel dip and things took longer, but that's
just from my experiences, no science behind it.