Pistol snapping at BTA

Did you ever get an answer to this? All of a sudden my anemone started to recoil, look kind of sick, then come back. It started doing it over and over. Now that I saw your post it triggered something that I did. I recently added a pistol shrimp that someone gave to me. I hear the shrimp "popping" but never put the two together. My BTA's foot is on the bottom of a rock touching the sand and I think the shrimp is trying to dig where the foot is attached. I believe this is what is happening to mine.