Strong but irregular contractions?

I'm 40+1 weeks today. I've had braxton hicks contractions on and off for several weeks now, and they've generally been painless or mild like light period cramping, and they weren't lasting very long.

Today I woke up and I lost my mucus plug. Ever since then I've been contracting all day, and the pain is getting progressively stronger. BUT the contractions still aren't coming at regular intervals. They look like this: 16, 17, 10, 21, 32, 11 mins apart. The pain feels really strong, though. My midwife said real labor contractions would be strong enough that I can't walk or talk through them, and that's definitely been the case for most of these.

Is it possible to be in early labor without regular contractions??