Braxton hicks contractions in waves

Hi,

Has anyone had Braxton hicks contractions that come in waves? The pain starts in my back then hip and around to my belly that tightens up. I had Braxton hicks all third trimester with my first baby but they weren’t painful. This time they hurt and I can feel them slowly coming on and getting more intense and then fading away. From what I remember, that is what real contractions felt like. I had a Fetal fibronectin test done last week and it came back positive but the dr is not concerned since my cervix is closed and the contractions aren’t consistent. I’m 33W 4D. Anyone experience something similar?? Thanks