Adobe Animate brush keeps changing color?

Hey, sorry if this is a dumb question but I'm pretty new to the current version of Animate

After I turned on onion skin, all of my frames (which were previously the same color) each turned a different color. Now every time I try to use the brush it just makes the strokes whatever ugly color it assigned to that frame instead of the one I want, no matter how much I try to change the brush color.

Anybody know how to fix this? (it may have to do with resetting the brush tool or presets, both of which I'm also having trouble with)

Thanks!