The Attack Starts At About The 2:18 Mark In This Video...

Colbie Caillat is best known for her 2007 hit single "Bubbly," but while performing that song in Pittsburgh on Tuesday night, the singer was in anything but a chipper mood. That's because while closing out the May 29 concert with the pop smash, Caillat was swarmed by a bunch of flying insects.

"Oh my goodness. I am traumatized from the bazillion bugs that were literally raining on me from the sky while singing on stage," Caillat wrote on her Facebook page.

The performance of "Bubbly" started innocently enough, with the crowd singing along to Caillat's vocals. Unfortunately, as you can see in the video above, bugs swooped down to interrupt the song. Caillat was forced to stop and take cover, but gamely returned and had the crowd help her finish the tune.

She is currently on tour with Gavin DeGraw.