The former Manchester United striker said: "It was a horrible, horrible debut in terms of the result. Obviously, it was nice to actually make my debut, but the result made it a very sore weekend.
"I am not going to lie, from a selfish point of view, it was good to be back.
"But from an unselfish point of view, I was devastated during and after the game.
"It was a long weekend for me. I couldn't even say I could take the dog out for a 45-minute walk because I haven't got a dog.
"My son didn't play football on Sunday either, so it was a long Sunday for me.
"But it is water under the bridge now. Such is life and we have got to try to crack on now and look towards Saturday."