Clown fish is not eating

[snoopusndmigllus]

Hey, I have recently bought a CK on saturday, it is now wednesday, and it hasnt eaten, or i havent seen it eat, im getting worried but he is swimming around a lot at night , but he gets scared when i drop in some food. im worried he isnt eating, he is around 2-4” and i was wondering how i can make him eat. Please and thank you