My labour was preceeded by a period of restlessness - I literally could not sit down.
Contractions felt like pretty strong period pain to start with, in both belly and back. Gradually intensified as I tried to sleep. Active labour started about 10 hours later, once I had walked up and down my very steep driveway about 6 times. I tried to use the positioning of my body to encourage DD to move her back to my front, which resulted in less back pain.
I lost my plug bit by bit as labour progressed - could see little streaks of it on the paper each time I peed.
My waters were broken for me by the midwife when I arrived at hospital - I was 6cm dilated.