How do you grow back eye brow hair really fast, within 3 weeks?

Sorry you can't grow them any quicker but three weeks will be good amount of time to grow back a little. You should try to buy an eyebrow pencil or eyeliner that matches as close as possible and just kinda poke the color into your eyebrows. Don't draw them on they will look really fake just kinda feather the color in so they look fuller until they grow back all the way. I have over plucked MANY a times.. It's sucks.