contractions...in my back?

So I'm having contractions in my back. It's been on and off all day and it's starting to make me feel a bit sick. It started yesterday but wasn't as bad. I didn't even realize it much until this morning. It feels exactly like the pain I had during a past miscarriage a few years ago. Just not as strong yet. I called the nurse and she told me not to come in unless I can't physically handle the pain. She said it just sounds like sporadic contractions and might mean nothing 😥 It's hard to time it because the pain is pretty constant. I hope this either stops soon or progresses to active labor because this is so annoying. I just want to get it over with 😓 anyone else have this yet, or with a past pregnancy!? I'm 37 weeks.