Contractions - 33 weeks

So since about 28 weeks or so I have episodes where I have contractions consistently for an hour and then they go away. Today they were every 5-10 minutes and started getting more painful. This is my third pregnancy, I had an episode with my second and got checked out, they chalked it up to being dehydrated. I am def. not dehydrated this time around, all I do is drink water/Gatorade all day. Anyone have this happen? I honestly started getting sick to my stomach they were getting so frequent. And I was getting bad lower back pain with them as well.