Not to worry.
It's normal for the long, white, early pistils to draw back a little.
And there are several reasons for color change of the pistils
The real bud fattening occurs around the 7nth week.
Post pics if you can, just in case something bad did happen.

Aloha,
Weezard
Weezard Reviewed by Weezard on . My Buds look like they have shrunk! I am about 5 weeks into the flowering stage and in the last few days my Buds look like they have shrunk to about 1/4 of their original size. They were white fluffy strands and now they are compressed and changed color. Not to mention how much smaller they look now! I will post photos shortly. Please Help! Sincerely, Steven K. Rating: 5