If the ER can't find anything in my eye, does that mean there's nothing there?

Here is a question: Did they look at your eyes with a slit lamp? This is an instrument found in every eye doctors office where you put your chin in a chin rest and they shine a narrow beam of light in your eye. Some well equipped emergency rooms have one. If I was forced to remove foreign bodies without one, I would have very little confidence in what I was doing even though I have been trained to do this and have quite a bit of experience.