Brown Discharge

Hello po. I am currently in my 36weeks of pregnancy. May lumabas po na brown discharge sakin kanina and it smells like mens. Medyo sumasakit na din tiyan ko at naninigas. Pero wala pa naman pananakit ng balakang. Is this a sign of labor po? Ano po dapat ko gawin? Tomorrow is my last ultrasound para macheck if kaya ko inormal si baby. Hintayin ko nalang ba yon? #advicepls