First time caller

This is my first ever plant, went for an auto CBD lemon potion from Barneys. I'm in about week 8 at the moment, another couple weeks and it should be time to harvest. I planted it in soil, and thus in its early days suffered some nute burn,but grew out of it fairly sharply. I started it under cfl then added in a small full spectrum LED. I did give it some tomrite nutrients, however the rust spots appeared quickly after, so stopped it, so its pretty much had no nutrients. All in all, everything is looking decent, apart from the rust. The pics are when I got it out to flush to try and see if it is Ph problem. If anyone has knowledge of the rusty brown bits, I would really appreciate their feedback. Thanks folks.