Labor started at 38+2, had him 38+4. The main sign was contractions that started to come regularly and didn't stop if I moved. But, I had felt great all day, went to Lowe's for paint, waddled around the whole store. I think I had diarrhea the day earlier. That evening I remember feeling weird but nothing I could describe. Then I felt the first faint contraction and knew. After that it was back pain, horrendous cramps, waves of pain, etc, off to L&D at 4 am and while my contractions were perfect, I wasn't dilating. So got sent home, went to the movies, tried to relax and shower and eat, then back to the hospital the next morning and yay, dilation!