there's so much purple it could be genetics... low p is another option. Though looks like some of those leaves have some blueish hue to them? that would point more toward low p than genetics.
all the stress could be why it flowered early.. but no guarantees on that either...
You got soemthing else going on cause that doesn't explain the paling ofleaves.. coudl be high k or low N. a leaf symptom chart is all i reference.. you'll have to consider how you have fed them to eliminate less likely possibilities... if you don't have one, go google marijuana leaf symptom chart .. good ones explain difference between mobil / immobile as well as numerous pictures to show symtpoms visibly.
concentration as well as ratio are important.. 7-8-15 ratio or 8-8-15 is a good starting point for npk... that's for a soilless/hydro context.. . relative to soil, you have to consider what is in the soil already vs providing 100% in fertilizer but understanding teh overall concept can still help in soil too.
I regularly grow 6-7 strains and use 1 reservoir with 1 mix of nutes... The only time i see issues is with retarded plants. I know becauase i've grwon 100s and from many different strains with virtually no nute problems in 4 years .. definitely nothing more than very minor tweaks.. probably as much related to seasonal differences since the dry nutes can absorb water from atmosphere and change the g/gal doseage on me. (i know i need to weigh out less ca-nitrate in winter vs late summer.. have notes to account for it and a history of this consistent need due to results in notes)
so, the idea that each plant has esoteric feeding requirements is nonsense, because vast majority do not... a genetically flawed plant might be... or a poorly selected set of parents with esoteric feeding, which is 100% a self-inclicted problem and easily avoided. inconsistent results point more toward an imbalance of fertilizer more often than not.