I got grounded for farting next to a fan?

We were having a family reunion and it was very hot (our AC broke down last week). Everyone was eating and I tried to casually bust one out, I charted instead. And just when I did, my cousin turned on the fan that was right behind me. Everyone looked at me with disgust as the smell of my fart filled the room. I cracked a little chuckle, but apparently smelling other peoples farts while eating isn't funny. I said sorry, and I tried to explain but I couldn't stop laughing. I still got grounded. Like cmon seriously? How do I tell my parents to grow up, and lighten up a bit?