I don't think I've ever heard a native speaker say it, but I could definitely imagine it coming out of a native speaker's mouth with that pregnant pause, specifically. Like an acknowledgment that you're about to say something a bit grammatically awkward.

I only mentioned it because I used to think correcting people's English was rude, until I had a long work engagement with a French guy whose English was pretty good but not quite native. He insisted that I correct his written English if I saw a mistake (i.e. in documentation, proposals, etc.), otherwise he wouldn't learn where it was wrong and how to improve it.