Contractions began

Cori

I went to my weekly NST today and was told by the nurse that I’m definitively having contractions but they aren’t regular enough to do anything about it yet. I have never felt contractions or BH before because my 2 1/2 year old came via c section at 39 weeks. Is there a standard ‘window’ of time once contractions begin when baby comes? What was everyone’s experience like with past pregnancies?