Hey there so just a couple things...1st the nitrogen claw, i think if you back off the N intake like you mentioned it should calm down, it didn't look like you'd gotten to the point of no return.
Regarding the red stems etc. No one seems to have mentioned that a phosphorus deficiency will usually cause this, along with the dark coloring on leaves and then into having some spots as well. Often mixed up with other deficiencies. But you mentioned doing a ph'd flush for a week...maybe with her headed into flowering it threw her off since they're very P hungry during those first weeks of flowering? I'd up the tiger bloom to a teaspoon and watch for a change. I have some sour stompers who were having excessive red and as i increased the tiger the red/purple became far less intense. Good luck with the grow, don't give up on her yet there's still lots of time to show what she's got.✌️