Can someone explain where I could have improved this game in order for me to learn from my mistakes?

I just played a game and I thought it was an easy win but somehow we lost it. I played panth, ganked lanes, stole a dragon, and back doored an inhibitor can someone look at this match history and tell me where did I go wrong this game? I'm not being satirical but rather I do want to know what I could have done better? If pros carry themselves out of these ranks so can I but I have to be doing something wrong at the moment. http://matchhistory.na.leagueoflegends.com/en/#match-details/NA1/2439082586/203123112?tab=overview