The 33-year-old Radio 1 "Breakfast Show" presenter said he knows he can redeem himself on the next episode of the show, reported FemaleFirst.
"Certain days you're like, 'God, I'm rubbish at this!' But the great thing is, you can do it again the next day," Grimshaw said.
The host said he had invited many bigwigs on his show nd there have been times they were not in a good mood, like the one time Justin Bieber was "tired".
"He was like, 'I'm tired!' and I was like, 'We're all tired!', he was not even pretending that he was not being grumpy," he said.