The broadcaster told The Hits drive show hosts Stacey Morrison and Paul Flynn this afternoon that he was exhausted after the show ended on May 29.
When asked if he was happy, Campbell replied: "Uh no, happy would be overstating it. That was ... it was tough. We worked really hard to save the programme, but, you know, how am I feeling? I was exhausted afterwards. I've just had a quiet two or three weeks, really, really quiet actually. Just kind of taking stock."
He said he "kind of grew up" at TV3, having worked there for 24 years.
"It meant a lot to me, that place, and if you walk away from that without feeling some sense of loss, then you're probably a bit too shallow to be involved in the business really.
"I've kind of been coming to grips with it. Some of my beautiful colleagues are still there, some wonderful people are still there that I love to bits, but I've got dreams for stuff I want to do now, really good and important stuff, so I'm going to work on that.
"Life goes on but it's been a tough few weeks."
Campbell said the outpouring of support for him and the show had been "really lovely".
Earlier today, it was announced Campbell would join the Sky Sport presenting team for next month's historic All Blacks test in Apia.
He will join usual presenters and commentators Grant Nisbett, Justin Marshall, Jeff Wilson and Ken Laban.
"The fact that we never played in Samoa ever just seemed wrong so we just pushed hard for it to happen," Campbell told The Hits.
"It would be wonderful to be a part of. It was really lovely to hear from Sky. I've never worked with them ever."
When asked if he got to do any commentary as well, Campbell said: "If they know what's good for them Flynny, they won't let me anywhere near. I don't think I'll be calling the game itself. I think that could be disastrous."
Sky said Campbell was a rugby fanatic who had been the driving force between a vocal campaign to get the All Blacks to play their first ever match in the Samoan capital.
Campbell also reflected on the late Jerry Collins saying: "I liked him. I knew him from Wellington. I'm a hardcore Hurricanes fan. The thing about Jerry was that he didn't conform to the professional norms."
