Hey abecsta, thats interesting... About 4 yrs ago I had 10 clones (afghan kush), 8 i grew inside my greenhouse and 2 outside... the 8 inside matured faster and the hairs browned as the plants matured... The 2 outside had these pink hairs like yours and had way more leafy buds and took a few weeks longer to mature but I just pulled them early as couldnt be bothered waiting... So maybe it has something to do with colder temperatures causing the pistils to go pink? Just a thought.. :L