Texture painting doesn't work

Hey, I am trying to paint hair using the texture painter tool. I have a Manuel Bastioni Lab character and I have shaped the hair by first extruding the scalp and then sculpting it. The problem is that when I paint the hair, it doesn’t show up properly in object mode. Let’s say I painted the hair pink, what I would see is the tiniest tinge of pink that’s barely visible and it doesn’t cover the default hair stubble so it kind of paints underneath the skin. Can anyone help?