Tightening for over an hour

I’m 35 weeks and been having stomach tightening for over an hour for the past weeks. I’m not sure if its normal. I’m not even sure what’s contractions because the braxton hicks i have are painful and my doctors been brushing it off as normal. Everything’s been said to be normal that i guess i’ll only rush to L&D even my water burst or i start bleeding.

I just want to know if you ladies to have tightenings for more than an hour that doesn’t goes off my standing, moving around or changing positions.