All of the blue and red/orange brushes aren't doing anything when applied to the upper part of my hair object mesh. I've tried flipping the normals and recalculating them, didn't change it. Trying it with dynamic topology off also didn't fix it. The brushes seem to occasionally work on the bottom part of my mesh, and I went inside of the mesh once and the inflate brush worked from the inside out.
Go to object mode, select the mesh, press Ctrl + A, then choose Scale.