This is my white widow in its 5th week of flower outdoor in November in San Diego. Everything was going well until I checked my plants and this is what I found... I believe its nitrogen but want a second opinion!!!!!
Yep, I think you are right.......
I had a Sativa dominant plant, looked just like your leafs, right next to an Indica dominant plant, and throughout the whole outdoor process, had to periodically give the Sativa plant my reg. nutes with N, in addition to the bloom nutes I was feeding both of them, but the Indica was fine without.
Also, be careful/ aware for rust colored spots on the leaves, that was another thing my Sativa had, but the Indica did not.
A little extra dose of Potassium and she was OK.