yes they move around at will . your main issue may be that your tank is a bit young for an anemone - 6 months may have been better. Make sure you keep up on your water perimeters. I have had some anemones that stay put from day 1 and stay exactly where I put them and others that move in and out of the rocks and hidden places for a month before settling down. if it stays hidden for more that a week you may want to turn the rock around so its getting light. Also be mindful of your pumps and wave makers they can wander up an get sucked in to pieces which would probably crash your tank. Some people cover filters and intakes with sponge or mesh to prevent this from happening. Good luck
