I just recently got one myself and it hid for a while (1 week) before it came out. I know it's kinda dissapointing to drop some change on something that hides for over a week but it'll come around. Now my RBTA is hosting a skunk and comes out every day. I wouldn't worry about too much unless it goes on for a few weeks. Even then, you can try to spot feed it with mysis or such to coax it out to ensure it's getting some nutrients. It's probably also stressed as well intially.
HTHs,
Minh