Deficiency?

Ok thanks I gave her some cal mag last night, she looks like she was perking up! I also realised I believe I was definitely not watering enough for a 5 G bucket, so I finally gave her alot of water, like 57 oz.

possibly pH problem. Check the runoff. if it is not within like 6.5 range. give fresh water. also don't overwater bc it can suffocate the roots over time. but if you are over watering usually the whole plant is droopy, if underwatering the leaves will feel flimsy. If you pH is still off after the fresh water flush then you probably need more calcium. do this. 1 gal of water and an air pump. put in 1 tbsp of molasses, a handful of kelp meal, and 1/4 cup of crushed egg shells. boil the egg shells in water for a few minutes and add to the one gallon kelp and molasses mix. brew this for 24 hours. dilute it for to 50% for a foliar spray or just water with that whole gallon you made. let me know how it goes for you. and if somebody would like to correct me on this go ahead, after all we never stop learning. but i've used this and it has help me clear my sick plant up