do you always talk like a retard?? how old are you 15?Did the temperature drop much? Did you feed it anything new or change nutes before problem started? Is the plant in veg or flowering?
Reason mon ask is becuse mon has seen leaves do that when the temps get down low however mon has seen it happen while a plant was in flower and nutes were changed, it happen fast while leafs where turning purple so was hairs glowing hot pink.......mon never figured it out but backed off with the new stuff and hairs went back to white after a week or so....mon didn't like it, mon thought maybe dyes in new nutes.
Or maybe you should stop trying to give out advice since you clearly dont know anything.The leaf doesn't look damaged by the deficiency (if there is one)
Maybe it's just turning purple?