Preterm Labor

Crysta
35 weeks and in physical pain from labor pains. No matter what I do I can't get them to subside( hitting me every 2 to three hours). Talked to the dr and they said just to drink lots of water (which I already do) and rest. I'm doing the best I can. This isn't my first baby, and I was in labor for weeks with no change with my older two. Just wasn't ever this painful. Any other moms have any tips?