Is the egg song for eggs only?

So I think I know what the egg song sounds like....from youtube videos.....So my hubby and I were attempting to work in the coop without letting the girls out due to rain. He was drilling and hammering and they did not care. Then he went to measure something and when he let go of the measuring tape and it went flying back the noise freaked them out big time and they started singing the egg song. Only two of them though and the two I think will lay soon. Coincidence? Do they sing the egg song out of distress?