I am a doula located in Beaverton, OR and I can assure you that you can be dilated for weeks before your baby arrives. I have also had a client personally that was 75% effaced for some time before she ever went in to labor, though she had hoped she would at the time and she too was 3cm for which she will decare "forever". It is good to be dilated early. Once you hit 37 weeks you are pretty much in the clear.
Best of luck to you and your family. Enjoy the weekend and try to stay focused on anything BUT labor.
T. Nelson CD