1. A female plant from normal seeds has produced 2-3 seeds by the end of the harvest without any male plants present? 2. Can pollen from other plants outside make it's way through the ducting and possibly pollinate a female? 3. And finally can these seeds be used to grow a female plant that won't hermie?
1. It got introduced to male pollen, or it hermied. 2. Yes. This is why it's important to sex each plant and determine sex early. Then, you should get rid of the male plants completely so it is impossible for a chance of pollinating. 3. Maybe, you can't tell until they grow and mature.