Those deep veins, in the leaves tell me shes well watered, perhaps too much ..?
Drooping like this, at worst is root rot, a fungal infection in the roots, bought in by the soil
the clue is in the smell of the soil, it may smell like rotten eggs or stinky socks
another clue ..like u said is the fact she droops when the light is on,
like something is stopping the roots acting on..?
what I'd do ...return he to veg for 7-10 days,
first pot up to another bigger pot adding 30% perlite or clean river sand to the wet FFOF
this gives much needed air to that soil
smell that soil, compare..??
FFOF is a quality soil and I've never heard of growers getting Root Rot from FFOF,
so maybe you got it from your water..?
perhaps I'm wrong and the room just gets hot ..? ensure you have a temp, and humidity gauge in there
along with a small fan
above all let us know how you go
now is a good time to take a clone
6-12 inches long, dip in honey and to a darkened cup of water for 10 days at 77f
cross fingers and good luck
When you transplant her...give her a half a dose of cal/mag with the watering. Make sure the soil isnt too too dry during transplant...it wont shock that way. I do see signs of over watering stress on bottom leaves as well.
