lower leaves on 4 week old plant look limp, hang down, sloppy. weird. how come?

Nothing related to Nitrogen here as the soil will provide enough nutrients for the 3 next weeks. It's looks like an over watering to me , you have a medium too moist so the young roots can be harmed by an excess of water. They can have been stressed by the transplant , if so it's because you did break some roots because it's never happens to me when I'm transplanting but when I was a young grower I had many bad tranplant with broken roots and excess of water like yours , only time could sort your issue as the roots will start to grow again and the water will evaporate quickly with the sunlight you are giving to them . Ps : don't transplant autos is the main advices

Both have a bit of a claw on the tips of the top grow. You said the ground is high in nitrogen so might be some nitrogen toxicity. You can flush with plain water to drain some of the nutes out or just water regularly and wait it out. Might be from overpotting as well. I'm still quite the noob myself so dont take whatever I say as 100% the truth, but I try to think of them as the living beings they are. If you overeat you get sick as well, catch my drift? Good luck.

could be over watering i would guess and if it gets like that only before lights off there just getting ready for bed but when you put them in a big pot it takes much longer to dry out so only use small amounts of water around the main stalk dont soak it all good luck

Dont worry about the lower growth, focus more on the new growth