"I can't believe I'm involved with the Under-21's, and at 18," he told the official Leeds website.
"The Leeds secretary (Ian Silvester) came up to me after Saturday's game and said 'congratulations'.
"I said 'What for?' and he told me I was with the Under-21's. I was straight on the phone to my mum.
"I couldn't believe it. I've only played four games for England at other levels and I've not played at senior level for Leeds yet, other than 20 minutes in a friendly, so to get into the Under-21's is amazing.
"To think, when I arrived at Leeds last summer I was fifth choice. Obviously, I've been working hard, but from that to reserves and now the Under-21's, I'm almost lost for words.
"I was sitting on the bus on Monday with the Under-21 lads and I was looking at the other players like Jermaine Defoe and Jermaine Jenas. I'm just stunned I'm involved."