The 28-year-old once claimed that he wanted to be the best striker in the world, but things haven't turned out as well as he would have hoped them to.
The Danish striker has been the subject of a lot of ridicule over the years by fans over his infamous comments but now he wants to reboot his career and focus only on football at Forest.
He said: "I pictured my career going in a different way, but it didn't.
"So I'm going to make the best out of the rest of my career and do the best I can. There are many goals I have set myself over the years. Many things I have said and been killed for.
"I actually don't regret saying I want to be the best striker in the world, because that's what everyone wants. It's just that no one wants to say it.
"It has haunted me.
"I was very young and I might have said it too early, before I'd proved I was in that category – or could get in that category.
"But I'm here now and I want to reboot, and get back to just playing.
"I am not saying I have never done anything wrong, because I have. But I know football makes me happy whatever level I play and I think I'll play football all my life.
"Six months out of the game can seem like a long time and, for me, it seemed like five years."