Auto seeds

You might ha e a sneaky hermaphrodite in your grow, or there's a male or hermaphrodite outside in your area.. Pollen can easily travel a couple of kilometers, and you can easily bring it inside yourself. I would only keep the seeds to grow outside and not spend much time on them other than checking for pollen sacs. If it's a male, then there's a 50/50 chance of males, and if it's a hermaphrodite, tey'll likely end up as hermies.