By the way, you can put peroxide undiluted into the plants for fungus gnats. Not everyday, not like you are watering. But it's already a very weak solution.
Anytime you spray a soap product on a leaf, you need to follow it up with a plain water spray. If you coat the plant's leaves, you are clogging the stomata, and interfering with proper respiration. (yes, plants breathe) In short, you are suffocating your plants. Had they been outdoors under the sun, you would have seen this happen on an accelerated timeline.
You will probably get new leaves, as it's doubtful that you've killed the plants. But next time you spray with soap, leave it on the plant for 20 minutes, and then give a moderate pressure spray of straight water, to rinse the soap from the leaves.
If you are trying to grow plants indoors, you need to be prepared in advance for these sort of battles. At the very least, you need to have a shower or wash basin, where you can do spray downs for pests.