In my experience, before mine started, maybe about 12-15 hours before I got what I consider to be a warning shot, first time it was brown and the second time it was bright red. I was examined just after the second time warning shot, and my cervix was still closed:
Everyone is different though and mine were both similar in some ways and very different in others - weird because they were both at exactly the gestation.
Hope you've been doing ok, I've been there twice so more than happy to be a sounding board. Xx