I would guess the humidity is too low with the fan blowing directly on the buds. Maybe move the fan.
Also itās possible youāre overwatering or underwatering the plant.
Also its possible you had a few pollen sacs grow somewhere on the plant and a couple hairs got pollinated
Donāt stress it to much
Don't get caught up in the hairs, they're going to express how their genetically programmed to do I would suggest getting a high magnification loop and paying attention to the development of the trichome in stalk production.
Can be normal progression. If it happens too early it can be indicative of potential problems -- wind burn/environmental issues or even pollination.
If you see them turn too early, it's a good reason to give a good inspection.
your pistils can change color prematurely from having a fan too strong and too close but they can also change color from just being touched and/or bumped.
they will also change color from pollination.
but also at a certain point they just naturally mature and change color.
beautiful looking plant with beautiful chunky pistils
best of luckš¤šŖ
Pistils turning brown is a normal process. Unless you need the whole wheres and why's then:
Google "pistils turning brown."
Organoman answered similar question 4 years ago.