What is the problem? Help pls

I recently used neem oil and insecticide on my plants to get rid of the gnats and now I'm noticing some discoloration and clawing on the tips of some of my plants. I'm assuming it's probably a lock out or possibly nutrient burn but I'm new to this and I'm uncertain.

REALLY hard to diagnose anything under your blurples, can you get a shot under some more "normal" lighting?

Sorry, here are some more in better lighting

I am no expert, but with the damage looking like it is only on the edges the neem oil may have been a factor. When, in her light cycle, did you treat her? If the oil hadn't had sufficient time to be fully absorbed, by the time the lights come on, it can basically deep fry the edges. To me, that looks like external damage. Might consider easing up on the N, that leaf is looking pretty dark compared to the newer growth. Are you using a calcium solution? Your newer growth is looking a little yellow.

Good advice from Johiem. I'll just add that if the pest problem is very bad gnat larvae could be hurting the roots and showing up as a deficiency/toxicity.