I went overboard with the DE the other day
I doubt the pistils will stay white when coated with diatomaceous earth, so that (and/or the light being to close) could be a reason.I’m not seeing to many white pistols
What Melville said. The DE stays in the buds as they grow and won't wash off at harvest. Some folks don't have a problem with that but it's certainly not best-practices to inhale it deeply into your lungs.I didn't realize you were planning on spraying it on the plant in flower. Diatomaceous earth can irritate your lungs if inhaled. I'm not sure if there's enough there to be a problem, or how much will still be there at harvest, but you might want to consider using that plant for edibles.
On the other hand, the buds aren't very big and it hasn't been long since you sprayed, so you could take it out to the yard and put the hose on "mist" and really rinse everything off. That's probably the best approach if you want to keep them for smoking.