I was having labour pains at 35+6 which were mostly back pain (with a bit of period like pain) coming and going, and I was very irritable, and upset cause I didn't know what it was.

I rang the hospital, and went in for monitoring and was having contractions about every 3 mins.. Managed to stop them, but sounds quite similar. I also wasn't supposed to have a natural birth, so they were more keen to get me in for monitoring.

I would be getting them checked especially if there is a danger of her having her baby naturally.