If you have thrips, what will destroy them, or so I'm told, is this:
I purchased mine while on vacation expecting to be facing an infestation when I returned, because it was obvious I had them when I left town for two months. Before I left I did a liberal dressing of neem meal. Powerful stuff if not well filtered. Powerful enough apparently, that it kicked out the thrip population. But I have this bottle on reserve should I have the problem arise again.
When using diatomaceous earth you want to puff it on. A fine dusting makes it nearly impossible for the insects to avoid the sharp edges of the crushed fossilized skeletons. If you think about it, you can see how over-application would create possibilities for pieces to lock together and form a kind of walkway through the shards. See where I'm going here?
I use this bottle as my puffer. There are special puffer bottles made for DE.
The DE you forked into your soil will not help much with your pest control - think sharp pieces now buried in soft soil - but it will add valuable silicon to the soil. I doubt you needed that much, but no harm done.
Puffing that fine dusting on is much more effective. Make the pot an impenetrable field of shards.
Wear a mask when you play with DE. I shouldn't have to tell you that, but one never knows.