What should I do ?

There is nothing you can do at this stage, the pollen that made those seeds would have been released about 3-4 weeks ago. No doubt there were one or more male flowers somewhere on this plant which escaped from your eyes. This was not due to the stress of heavy flowers, but may have been due to the stress caused by the defoliation you did, or perhaps the 20 hour light schedule you seem to be using. 18/6 is much more plant friendly and the optimum lighting schedule for all cannabis, auto flowers or photoperiod plants in vegetative growth. Defoliation just reduces your plants ability to produce energy and slows growth. It also causes a big metabolic shock to your plant, especially if done during flowering and this sort of metabolic shock can cause plants to do strange things, like grow male flowers. If your plant was a V Eight racing car at Le Mans, defoliation is the equivalent of disconnecting 3 or 4 cylinders and then expecting the car to do the same lap times. So at this stage I would not worry too much, she is that close to, if not ready for harvest, that doing anything now will not have any time to affect any changes. In future, growing at 18/6 will give you plants just as big as they will ever get, but they will be healthier due to getting the correct amount of "sleep" and not defoliating your plant will ensure it is able to make the most amount of energy she can, which means she will grow the fastest and biggest too. Just remember - Maximum amount of healthy green leaves = maximum energy production = maximum growth and fastest growth. Hope this helps, Organoman.