The 20-year-old, who advanced to the final with his last throw of 65.28 metres in qualifying, was unable to replicate the same distance with his first throw of 61.03m the best he could produce in front of a capacity crowd at the Olympic Stadium.
And the Croydon-based former rugby player was disappointed to not finish higher and admitted he has still has plenty to learn at the top level.
"It's been a good couple of years,” he said. “I felt relaxed. I was trying too hard.
"Something went wrong, I've nothing else to say.
"I've got lessons to learn. I gave my all, but maybe too much. I'm obviously disappointed."