At 28 weeks it was 11 at night and I was having Lower abdominal cramps that was irregular and figured it was constipation pain. They hurt but I could handle it, I went to bed and woke up at 5 in the morning hurting pretty bad so I figured I needed to go to the bathroom and i got up and went and didn't hurt after that and I laid back down. Then around 12 is when I got up because I was being woken up to constant cramps that hurt pretty bad to the point I couldn't sleep. So I got up and within 20 minutes of walking they got so bad I called my dr and told them about it and they said I needed to be checked into labor and delivery to see what's going on and the pain progressed so so bad. They hooked me up to the monitors and I was having contractions. If they get worse, and are low and sharp and maybe in your thighs and back its contractions.