I need help

Woke up this morning with horrible cramping and dull aching from my back to my legs , hip and front of my abdomen too. Also was having some tightening which is better now that i drank a lot of water. I am worried about preterm labor and called the doctor. They said to rest, use hot packs, and drink more water. She said its probably sciatic nerve pain. Can anyone with experience please help me out? I still have the period like cramps and pain. Do you think I need to go to L & D? I am 29 weeks 3 days today.