What is a nice way to say I'M BUSY without saying I'M BUSY? REAL ESTATE DESIGN

I work out of a couple offices, although I would get more work done if I were at home or in a closed office, for a real estate office.

I get bombarded with a constant influx of projects that I compile on my own task list to maintain my own sanity and time management. I usually tell people 3-5 business day turnaround (not including weekends!) (it also varies per project). Some projects take precedence over others and I of course work on those first. Recently I have been swamped with not only projects but meetings, interruptions, etc etc that I feel as if I go backwards instead of forwards.

Agents tend to hover over my desk, even when I am on the phone or meeting with an actual person to say "where's my "this"?!" Seriously though... is there a nice way to say IM BUSY without sounding like a jerk. I tell people "I'm working on it and they just stare and then stomp off."

I just want to design and not deal with the diva drama.

Any advice is appreciated.