James was fielded in midfield as the Blues blew an early lead to lose 2-1 at Villa Park.
"It’s really disappointing to leave with nothing," James said afterwards in the mixed zone. "Especially when you consider had the lead at half-time, having started the game so well.
"In the second half, it was a different game. That’s what is frustrating I think. We worked hard all week on analysing Villa and where we could exploit them and I think we created many chances in the first half. In the second half, it was a totally different game.
"We’re very disappointed because I don’t think we deserved to lose the game. We created more than enough chances to add to Pedro’s opener and we’ve conceded two goals from our own collective mistakes as a team."
On his new position, James added: "Yes. it was a completely different position to what I’m used to but that doesn’t worry me, it’s somewhere I have experience playing in so it wasn’t anything new to me.
"Wherever the manager needs me, I’ll play there and give my all to help the team."