Mudskipper suddenly hiding during feeding time?

Basically what the title says. I've had my Indian Dwarf Mudskipper for about a year now and he's always been crazy about food, sometimes leaping up at my hands to try to snatch it before I set it down. Today I went to go feed him and he went and hid behind one of his rocks. I figured maybe I just spooked him so I waited and came back to try again, and he went to go hide again. For context I was feeding him the same type of food as usual, nothing he hasn't had before (frozen mysis shrimp thawed).