My doctor prescribed terbutaline for my "comfort" i was not in preterm labor. i never dilated nor had any effacement. why?

Not in labor: You likely didn't dilate because you weren't in preterm labor. There are no medications that will stop true preterm labor; the best we can do is slow things down to allow benefit of steroids to improve lung maturity. Current guidelines recommend against the use of medications beyond 48 hours for slowing contractions, there is no demonstrated benefit that justifies the risks of these medications.