TROLLING BANABLE?

So hey guys i have question here, Is trolling once in a normal banable? i never new a first time troll could be a just plan out banable offense? is it if you concede a certain amount of deaths you get banned? Because that recently happened to me and It said this "you have intentionally fed in these games" it showed one and in my match history as well it only shows 1, so im confused, if a one time thing is a 14 day ban worthy then shouldn't you receive a warning. If it is I would love to know for future tense and ill proudly serve my 14 day bans with no complains, But if its a one time thing how come my other teammate in my game didn't get banned aswell? when you look at his match history it shows more than 1 intent game. Id love to know more thanks, If a riot user can explain more better that would be good to, i dont want to get the wrong cognitive if because of right now i feel like thats an unjust ban but if its in the rules ill serve it proudly. Heres a link to my game they sent me http://matchhistory.na.leagueoflegends.com/en/#match-details/NA1/2410974066/43934297?tab=overview