Week 5 of an auto won’t be pre flower it’s just in flower. The auto stands for auto flower. Meaning it will flip itself when reaches a certain part of the plants life cycle. Or well that’s to the best of my knowledge. Stress at 5 weeks will also push it quicker as a defence mechanism. I’ve grown 2 autos that started flowering at around the 3 1/2 week mark and another that didn’t till 6 weeks. They were zkittlez auto Germed same time and in same tent /light schedule