When did they start? How did you tell the difference when real labor started? When did you go into actual labor vs when you started getting BH?

I'm 34.5 weeks, and have been feeling what I think are BH contractions for the last couple of weeks. (I never had them with DS1).

They're not painful, my stomach just gets really hard and tight all over for a few minutes and then softens. It happens quite frequently throughout the day now (and I"m sure overnight).