I'm 36 weeks +1 and am scheduled for a repeat csection may 16t . I lost a big chunk of mucus plug on Monday morningish. later started having contractions but nothing to big, next day suffered contractions the whole day and at night started with back contractions. This morning still having contractions, went to doctor they hooked me up to the monitor and it showed I was contracting just not significant strong ones. doctor checked my cervix no dilation, but she said I was in pre labor and to keep an eye on it. How long were you ( if you were) in pre labor before your true labor started?