Ouch my belly is so harrrrd!!! Why?

Braxton Hicks are supposed to last 2-3 minutes maybe 10 times a day, right?
Why my contractions last 1-2 or sometimes 3 hours without to stop AT ALL. Even if I lay down or change my activity, after lunch everyday I have a hard belly though the night.
I talked with my OB/GY but she doesn't know really why... #joke.
I'm 34 weeks.
Am I the only one?