the tentacles deflate a lot usually, its a way to release waste i think, there tentacles are 98% water i think so it will just absorb it back in. If they damage the tentacle it should heal but if they damage there foot/base then there probably goners.
They'll start moving themselves soon to find a place where the light is perfect, dont move them if you dont like where they are, only move them if you think something wrong will happen to them
No need to feed, if you really want to try feeding once a month with liquid invertebrate food or cyclopeze or baby brine shrimp, squirt the food near the tentacles. I dont think you will need to feed unless the anemone doesnt seem to be getting enough from the light