So last night, DH and I DTD. Immediately after, I started having contractions, not BH, but the real deal. They started in my back and worked their way around. Not too horribly strong, but some of them took my breath away. They lasted about 45 seconds and were coming every 2-2.5 minutes. I laid down and drank a glass of water. No change. So after about 45 minutes, I called my midwife. She had me take two Benadryl, drink 1/2 an alcoholic drink and take a bath. It didn't work immediately (I was still contracting 2 hours later), but it did put me to sleep and I woke up without contractions.
Anyway, I'm now on pelvic rest until 38 weeks.