I make the dumbest and usually most expensive mistakes when I'm tired and/or trying to do too many things at once. Then I get mad at myself, and rant, then depending on just how tired I am, sometimes I literally cry in frustration. Which usually leads to me hating my dh for a while because he thinks my rants are hilarious, which just makes me madder and I really hate crying for no good reason......which makes it worse. It's a vicious cycle.
Now I don't do anything except sew after 10pm, no cutting, no measuring, nothing that will take more than ripping some stitches to fix.
Light sanding, depending on how deep the cut is you might have to use a couple different grits of sandpaper, just make sure you use at least 120 or higher for last pass, I usually use 180, and some stain will fix the cuts in wood.