So confused???

Yesterday my water started breaking (definitely familiar with what that looks like- 2nd baby). We go to the hospital, the resident doctor ran several tests to see if any fluid was discharged- and could not find enough evidence that my water broke. Did an ultrasound and there was still plenty of amniotic fluid and baby was healthy. I was having mild contractions every 12 minutes, but was sent home because water didn’t completely ruptured and baby was healthy- I’m so confused why didn’t they admit me- what if I go into labor? Called my doctor she asked me to monitor contractions and to see if water continues to break. So far I am only having minor contractions. Any ideas if labor will start soon, I’m 37w and 2d.