35 and 1 and dilating!

Mandy • I am 34 pregnant w my second. A baby boy. My daughter, who is 4, was born a preemie and thus I'm a NICU Mom.
I had to go to the hospital since I am high risk and was contracting. Turns out I was obviously okay just taking precautions my doc told me to take. 
I was checked and told I was 1.5 cm dialated. Is there anything I can do to prevent further dialation? I clean a lot- am I too active.
My husband says I should start working out to make delivery easier. Since I am always hurting and my back is now worthless and can't even hardly lift my legs when I am laying down. What can I do?