my new betta, who i just got yesterday, doesnt seem to want to flare his fins when i show him his reflection. i picked him at the pet store because his fins were flared the whole time i was looking at the bettas and he kept darting around and seemed very active. but now when i show him a mirror he just darts away. he also hasnt eaten yet and seems to "sleep?" a lot. he does seem much healthier than my last betta but is this just from stress/ getting accustomed to the new tank or am i doing something wrong?