outdoor small leaves turning purple (4 weeks into flower)

[Buhdah]

the small leaves around my top bud are turning purple and there is a spot on one bigger leaf that is purple. about 4 weeks into flower. we have been having some cold nights this week (into the 40's). is this something i should be worried about? possible nute burn?
see picture.

 

[neongreen]

I think it's the cold affecting newer growth/smaller leaves first (smaller things loose heat quicker). It's definitely not nute burn. A few of mine are doing the same right now:

 

[Former Guest]

what are you feeding it? it looks like its just at the tips? or is there purple spots elsewhere forming as I thought I might have seen one where the fan leaf meets the stem. did this happen overnight or is it seem to be traveling?

 

[Buhdah]

im giving her Jacks 10-30-20 blossom booster every other feeding. straight water in between. it has happened over the last week maybe. only seems to be on the cola. this is the only plant i have, so i don't have anything to compare it too. also its a mystery seed, so i do not know the strain.

 

[Former Guest]

probably the cold. mines getting some on the very edges of just a few colas. just had to ask since you didn't say anything about what you're feeding her.