What's wrong with my male crown-tail betta?

[DrrRATS]

He's been acting a little strange lately. He used to follow me when I walked by but now he just sits there looking up. I've also noticed that his stomach is EXTREMELY large and there's this silvery thing underneath his gills. He flares at the other bettas and everything but is this normal?? O.O The ends of his fins are curled, and his back seems a little..... hunched??

If this has anything to do with my betta, he's from petco.

[psychobunny13]

Sounds like a combo of constipation, fungus, and fin rot, two of which are brought on by poor water quality. You should change his water more. For his stomach, give him 1/4 of a cooked and deshelled pea. Then fast him for 2 days. Start feeding him less than you usually do. Constipation is brought on by overfeeding. For the fungus and fin rot, give him something that cures bacterial and fungal infections like BettaFix, MelaFix, or Betta Revive.