need advice !!

in 40 weeks & 3 days pregnant, and at my last apt my doctor checked me and I still wasn't dilated at all. well ever since my due date (which was 3 days ago) I've been experiencing what feels like Braxton hicks but their a little bit more uncomfortable and a tad bit painful. my stomach gets rock hard and I have this dull back pain in my lower back. could this be the start of something hopefully? and I'm pretty sure I've been losing parts of my mucus plug the past 2 days.