Did you experience any signs that you could possibly be dilating? Or were you surprised after being told you were "x" cm dilated?

I've been having random lower back pain, pressure, shooting pains "down there," but it's not consistent at all so I have no idea if it's contractions, BH, or just normal pregnancy pains. (I'm 36w5d.)

Just wondering if those of you that were dilated before labor felt anything that made you think you could be progressing?