it could be mucus plug and nothing to worry about. it is one of the signs of dilation and/or effacing. moms can lose their mucus plug for weeks before labour. I have been losing it 1 week and counting. ranging from really jelly dark brown to snotty pink. our bodies can also reproduce the mucus.
Mucus plug have a little blood when it comes out. As for discharge it varies in colour from white, yellow, light green.