It won't hurt to try it once and if you don't like it call a pro. They sell popcorn ceiling mixture in various amounts (quarts to gallons) at any home improvement store. scrape off the old repair and recover it the new popcorn and paint to match.
The trick is to get the consistency of the popcorn distribution to match the rest of the ceiling (sometimes it "blown" on making an unnoticeable hand repair difficult)...it's only a few dollars for the stuff so i would try it oce myself to save a repair bill...it's the kind of thing that can be done numerous times.