Nick Jonas talks about the time he got an accidental erection on a red carpet

Nick Jonas demonstrates how he had to cover up on the red carpet.

If you're a male celebrity walking the red carpet in front of hundreds of photographers, the last thing you'd want is a random erection.

But that's exactly what happened to Nick Jonas at the Young Hollywood Awards in 2014.

As the 23-year-old singer explained to talk show host Jimmy Fallon last night, the surprise stiffy caught him off guard after he sampled a "weed lollipop" the night before.

"I woke up the next day ... everything's in slow motion," Jonas said. "So I'm panicking. I go back to bed and wake up a couple of hours later."

Feeling much better, Jonas arrived at the Young Hollywood Awards and started walking the red carpet.

"Out of nowhere I get a NARB," Jonas said. "All men get a NARB from time to time. A NARB is a Non Apparent Reason Boner."

Jimmy Fallon then displayed a photo of Jonas on the red carpet in which the singer is seen covering his private parts.

Nick Jonas standing very purposefully at the Young Hollywood Awards. Photo / Getty Images

Jonas later presented an award on stage and even though his NARB had dissipated, he was still struggling from the side effects of the "weed lollipop".

"So I'm presenting an award and Ansel Elgort's just won, he's really tall and I'm not," Jonas said.

"I get up and I stand on stage for probably 20 seconds without saying a word, just looking around. I pick up the microphone and I try and say a joke that wasn't in the script because I thought it was just going to be amazing."

But the joke wasn't amazing. In fact, Jonas could hardly speak and was barely able to deliver the punchline.

"I'm like, 'I would love to have the same problem as Ansel but I'm short ... er'," Jonas said on stage to the confusion of the crowd.