Disorganized, all over the place. Making numerous mistakes because your mind is on too many things at once and consequently none at all.
"Oh man! I figured out my finances wrong and overspent, then it turned out I bought the wrong thing and it'll be too late to return for an exchange. Then later I remembered I was supposed to meet somebody for coffee. I totally forgot."
"Man, you need to slow down. You're overworked and overwhelmed and you've become scatterbrained!"