Since you're going to be harvesting, there's nothing to be done at this point for your grow but for FUTURE grows, this plant has suffered a severe deficiency of potassium. Since you don't indicate any nutrient information here, it's impossible to tell why this has occured but in all likelihood, it was brought about by a nitrogen toxicity which locked out the potassium (and probably a lot of the phosphorus as well). When plants go into flower, during pre-flower, you want to start cutting back on the nitogen-heavy nutes and increasing the bloom nutes. At about the same time, you're going to want to be giving them periodic (once a week) doses of calmag and at about week 2 or 3 of flower, adding in a PK booster. Flowering plants are putting all their energy into the bud production and they need extra potassium and phosphorus to do that. Your plant was desperate for more of each which has most likely reduced your yield.... Your pH, btw, is perfect - and that's USUALLY where the problem lies when it comes to these deficiencies... so kudos to you for keeping it where it's supposed to be. Next time, just be aware of the changing requirements as the plants go into pre-flower and flower... you'll have happier plants and better harvests.
Good luck in trim jail!