My betta was acting a little abnormal this morning

[bosco]

I need some help! My betta was acting really strange this morning. I went to feed him his breakfast and he wasn't eating. Instead when he went to snag a pellet it almost seemed like he was attacking it. He would snap at it and it was so aggressive I could hear him thumping against the tank. I was sitting there watching him as I usually do while he eats and I just found it out of the blue. And also lately he has been flaring his gills A LOT..I meen excessively. He'll be swimming and they'll just flare out over and over. What is he doing? Anyway, I am new to Bettafish.com and I hope I can find some answers about the odd happenings of my crazy Bosco!