advice on labour please?

Sarah
So im due in 2 days.
Today for about the past hour and half I've been getting intense pain in my lower back. Almost feels like someone is squeezing a nerve then releasing.
I've tracked in my phone and at the minute they're all over the place I terms of length apart, as in sometimes 10 mins, then 8 then 10 then 6 mins etc...Each pain lasts approx 30-50 seconds. 
Could this be the start of labour? 
Should I call labour and delivery for advice? 
I have no tightening or tummy pain.