the red/orange pistil develop as the plant ripens, there's no controlling it and its a decent indicator of your plant approaching harvest time when they start to shrink and curl.
3 things a new grower should never do:
1. Listen to friends grow advice.........
2. jump right in without a clue
3. not read a decent grow book ( I recomend Read Spear's Marijuana Cultivation Reconsidered, he shoots doen a lot of grow myths that even some "experets" believe in )