Well you have certainly over watered it, stressed it and possibly scorched it when it was stressed. Short of doing a deep root moisture test you have to guess when its ok to return to regular watering. Once you feel it is safe to give it water again I would recommend fertilizing it with a moderate to high Nitrogen fertilizer, something that is 2-1-1 ratio, and has some trace nutrients too. Giving it a bit of shade might also not be a bad idea since it is clearly in a healing stage. Which also means you should keep a close eye on disease and insects since its more susceptible to it in this state. Good luck, keep us posted.

Gorgeous tree. A little leaf drop is common in the winter for container citrus kept indoors. This is particularly likely in northern regions. You can read into Winter Leaf Drop to learn more.

Hey Everyone! Thanks so much for all of your advice, and input. Apologies for my lack of activity recently. Shortly after I realized the fertilizer is what was killing the tree, I repotted it back to the container it came in, with fresh soil. I continued providing love (grow light, root booster, etc) for a couple more weeks until the entire fre tree was brown. Determined to have a lemon tree, I started 10 seedlings from an organic lemon. A couple weeks later I was at the nursery, and I mentioned my situation to an employee. She said I can bring the tree in and they'll exchange it for a new one. They get their next shipment of citrus trees in November, so I'll swap it then. I'm determined not to make the same mistakes with the new free as I did with the first one. I am going to keep a couple of the new lemon trees, and give the others away once they've matured a bit more. @Sunshine: Thanks for the advice regarding manure. I followed the advice of an employee at a local nursery. I should mention it was composted manure. The pot we chose was not only for decor, but also the size. Advice online suggests a white or light colour pot to keep the roots cool during summer. The pot has a 1" hole in the bottom (similar to terra cotta pots). The only reason I added styrofoam and gravel was to prevent the soil from sitting in water before any extra was able to drain. In hindsight, I realize it was unnecessary. I don't think the pot was a contributing factor to the issues the tree was suffering though. I definitely haven't given up. I'm not discouraged by my learning experience. In the end I'll have even more tree, because if not for this experience I wouldn't have started the seedlings.

Tropicofcancer, ok would horticultural oil have the same effect as the 3 in 1 organocide? You say its lighter so can that possibly mean less damage on the pests and they can possibly survive it? Also when you say alcohol, is it rubbing alcohol? I used a cylindrical tupperware and filled it with fir reptibark 5 times and then dumped in trash bag, then filled with sphagnum peat moss once then dumped in trash bag, then filled with perlite once then dumped in trash bag, then applied one teaspoon?(I forgot how much) garden lime and then mixed it all up in the trash bag. I repeated this same exact process until it filled the pot up where the citrus went in. During spring and summer I watered about once a week. I check the soil moisture by sticking my finger in as deep as I can and only water if its dry. It had super rocket fast drainage so no issues there. I am 100% sure I used the right dosage for it. It happened about 2 weeks after I sprayed it though. I don't have a greenhouse. I only sprayed this on my 3 citrus and thats it. I also sprayed it on my sedum which is planted outdoors. No problems there. What is safers soap?