Labour Can a 39weeks pregnant woman feel contractions leading to labour without seeing signs like mucus plug, spot (blood stain) etc?

What is contraction? How do one feel contraction or recognize it?

Thanks
You may experience deep and painful twinges, and practice contractions, known as Braxton-Hicks', particularly toward the end of pregnancy. It's easy to mistake these for the real thing, and you may find yourself rushing to the hospital when your body is really still practicing.