Get out of going to Work...

FTM and a preschool teacher that is due to start back at work July 26th. My due date is Aug 13th literally two weeks from our first day back and trying to figure out what I should say to my boss to let her know I'll come in and work for 1week then taking the last week to prepare before baby comes. Anyone had a similar experience? Did boss start your FMLA  Maternity Leave early or did she count that last week as sick/ vacation time?