Leaf curling cause - Humidity, nutrient or overwatering

Ooo not looking good here my friend this looks to me like a root system problem not getting enough air I would say. It does also look like shes going through bit of heat or light stress too which wont help things erm best course of action I think would be to try and disturb the soil top abit and then just flush with water until she looks abit better you may haveto pull of a few deal leaves but im sure she will pull through. Im only going on my own previous experience with symptoms similar to this I could be wrong. Best of luck either way :)