Beginning of labor?

Cecelia
FTM: on Wednesday I was 70% effaced, 1cm dilated and the doctor said she was feeling my baby's head so she was pretty sure the mucus plug was gone.
I never actually saw a "mucus plug" come out.
Tonight I just found some brownish red discharge on my panty liner.
Just wondering if this might be another indicator labor is starting, or just late pregnancy?
I know there's no definite answer, just looking for suggestions/advice/experience.