Some wall paint was accidentally brushed on the ceiling.The wall paint is acrylic low sheen and was applied 5 days ago.The ceiling paint was applied about 19 years ago and was probably a standard white latex covering. How to remedy?
You will need to match the ceiling paint color in order to touch up the wall paint. This will be very difficult as the age of the ceiling paint will have changed the overall color. You need to have this paint matched. Is there anything that has some of the ceiling paint on it? Any empty cans?
Unless a good match can be done you might have to either live with it or repaint the ceiling.