Goobie, what a timely post.... DD was called out this weekend on exactly the play that you described. I would not have worded it any differently. She rounded first looked for the ball, found it was with the pitcher and returned to first. PU said she hesitated too long.... Her hesitation was less than 1 second while she was finding who was in possession of the ball.
So the umpire called the play correctly, you just disagree with his judgement of "immediately" return or advance after stopping......