Mucus Plug

Hi ladies im a FTM & im 32 weeks & 4 days,, this morning i went to use the restroom & as i wiped i saw that i had lost some of my mucus plug.. i got a little worried & went to the birthing center with my husband,, everything was good the doctor told me i wasn't dilated or anything,, my question is how long after you start to lose your mucus plug you have to wait to go into labor?