I purchased a Eureka lemon tree at the Philadelphia Flower Show. The tree came in awful media which retained water and was very light. I watered the tree once I got home and it did not dry out by any means a week later. I assumed it was overwatered as the previous media it was in did not dry out whatsoever. The tree was also planted above the crown. I brushed off soil particles around the crown.

I have taken the tree and I had transferred it to a bigger pot with a roughly 1/2 coarse bark 1/4 peat moss, and 1/4 cacti/succulent mix. Before I put the plant in the new pot I checked for root rot. It did not show signs of rot, but the root sheath was easy to pull off which helped to confirm my overwatering. I did not water the plant after transplanting but will do so tomorrow. I wanted to let the root region to dry out before. Now, 3 days after transplanting I feel it is looking worse than before. Is this tree able to be recovered?

I attached a few pictures:

The things to note are the drooping leaves of the tree, of which the actual branches are starting to droop as well- could I have gone too far in the underwatering direction now? There are also a weird set of brown spots on the twig. I used my hand lens to show it.

Thanks in advance for the advice. This is my first time on a forum, or even caring for a citrus tree. I hope I can save my plant and let it grow happy