How long did it take from your first contraction to have your baby?

What were some of the earliest symptoms you had the day of labor? For some reason im worried ill go into labor today while we are having this crazy snow storm. Currently we have 15 inches of snow and counting. Thousands are without electricity and heat. There are cars in the middle of the road that people left there because they got stuck. Ive had some nausea and vomiting and some mild cramping YESTERDAY/early this morning, but so far nothing since. Is it safe to say that im probably fine and wont go into labor or is it a quicker process than that? How long was your experience between 1st contraction and actually giving birth?