lake 36 weeks pregnant with no BH contractions?

I'm 36 weeks pregnant and have had absolutely no Braxton Hicks contractions. I am at 0 station and my cervix has thinned. Should I have felt some contractions by now? I have tons of low pressure constantly and am very uncomfortable all the time. I have had some brown discharge (not really mucus like though). Also, the baby's heart rate went from 144 last week to 130 this week. Is this all normal? Will I go into labor soon? Should I be worried I BH contractions?there