Hopefully you can go back to your notes and check everything. Whatever your prob is, it's too late to fix it properly, due to it being deep in flowering. Use this as a learning experience. If I had to guess, I'd say it was under fertilized during the stretch, and then you pushed her too hard to compensate for that. Do you have a pic of week 2 or 3 of the flip. Can't rule out PH imbalance either. GL