My dog stomach was kinda big now the next day he is back to normal i know it isnt bloat?

i know it isnt bloat because bloat doenst go away like that but i think cause my little brother gave him to much doggie treats and he pood red (the doggie treats were red) but he did not .that day he did not poop alot. he has non of the symtoms of bloat he is a chiuaua but i just think he is fat but what do u think or could it be worms..... the last time i took my old chiuaua they did not let him out and but then he was put to sleep .he was going to bo okey but now he is gone R.I.P CHICO so could you give me a hand