How far into flower were you when you pollinated? I did the same thing recently and because I pollinated the lower most branches I just harvested the rest of the plant when it was ready. I did it to two different strains and the seeds were ready at different times... between 5-6 weeks for me. Letting the seeds continue to mature on the plant after cutting it down worked well for me... it's worth the experiment I think if your plants end up being ready to harvest before the seeds are viable.