Keep an eye on it. You may just be seeing calyxes. If they start to grow bigger, then you are seeing seeds.

Pollen can stay in the room after the responsible male is long gone..

Vacuum!

Buds don't really start to put on weight right away. No worries there.

The buds may end up a bit smaller because some of the energy the plant would be using to increase size is going into seed production.

And you may harvest a few days earlier as a result.