The singer describes the week of the new track's release as "the worst time ever", reported Digital Spy.
"I released it on April 12, and on April 13 I had a huge concert in Korea... So that week, it was like hell. On Friday, I had to release the single, and on Saturday, I had to release the video, and I had to do a 50,000-person stadium concert. And that same week, on Monday and Tuesday, I did the shooting (of the 'Gentleman' video).
Psy also admitted that he made a lot of changes to the song ahead of its release.
"I honestly changed this song so many times until the very last moment. I was not excited, I was terrible; I was so nervous. My only goal was to avoid being called a one-hit wonder.
"So that was a very nervous moment right before the premiere; and in two weeks, with 230 million views, I'm not a one-hit wonder. I'm really happy and relieved about that!"