I'm having the same thing (and mine also includes back pain, cramps, etc). Mine started at 31 weeks. I couldn't get the contrax to stop and I found that I was having to be still to get through them. So, off to the hospital where, of course, they immediately stopped as soon as they hooked me up to the monitor.
My midwife had the nurse check me (I was closed) and they did the FFN (I think that's the name of it) test. It came back fine. So, she said I had a 1 in 100 chance of having the baby within the next two weeks.
I saw the midwife a couple of days ago and explained that I'm still having the contrax. She said to watch them and if I'm concerned or have any other symptoms to call or go to the hospital. She said more than likely it is just that my uterus knows what it's doing with this second pregnancy and I probably won't go early.
It is scary. I experienced nothing like this with my first. I had already started dilating at 36 weeks and didn't even know it (no contrax that bothered me like these, actually not a lot of BH at all). By the time I gave birth at 40w5d I had been walking around at 3 cm, completely effaced with bulging waters for three weeks.
I WOHM, too, and if traffic is good it takes me 45 minutes to an hour to get back home or to the hospital I'd like to deliver at. So, I'm watching closely when I'm at work and considering taking my leave a week or two early. With my first pregnancy I worked until after lunch, left to go see the midwife to confirm I was in labor, went to the hospital right after and then had my son in the middle of the night. I don't think I want to cut it that close this time.
I'm sending good longer-in-the-oven vibes your way!