sometimes the plants put out seeds naturally, just tryin to stay alive! If u had male flowers or pods then it would be because of pollenation, but it sounds like it came natural. Give the seeds an extra week to ensure that it will be optimal for growing, remember a good seed has tiger stripes! to get better crystal formalization put the plant in pitch black for a day and chop it the next mornin. and if there was a male flower in there that pollenized your female plants, the seeds should come out feminized, but may turn up hermaphrodite in the end.