How do you know when it’s time?

Von

Hi! I’m currently 38 weeks and 3 days. I’ve been getting tightening on my belly for the past 2 weeks that’s been gradually becoming more frequent. Yesterday was the first time I started feeling pressure towards my lower pelvis and rectum, as well as intermittent cramps and constant back aches. It actually feels like I’m on my period.

However, I don’t see my mucus plug, blood, or any gush of water.