It might be trying to self pollinate because it's stressed for some reason. I would try to remove the pollen sacs as carefully as you can, and just know that you'll probably wind up with some seeds. Not the end of the world though, just a bit lighter on the yield. I've smoked some great weed that had a few seeds in it, I am under the impression that yield suffers much more than potency when buds get seeded. (THC is used by the plant to protect itself, there's no real reason that it would produce much less of it. Less total maybe, because there may be less buds, but the bud that are there should still be good)