labor or not

So I'm 37 weeks. And I'm not sure weather to call my health care provider or go in to labor delivery. Where I live at its 9:00am. I don't know if it's relevant or not but I have an anterior placenta. My back has been hurting non stop since 5am yesterday. Nothing help. Drinking water, warm bath and shower. And I noticed milk leaking from my right breast. Do you think I'm in labor and should call or go in. Or I'm overreacting