Updated

After suffering a painful-sounding injury last week, Gwen Stefani was back on stage Tuesday night performing on “The Voice.” According to her beau, Blake Shelton, the singer flew on an airplane with a head cold, and the pressure in the cabin caused her eardrum to burst. Yikes.

"I mean pop — blow your eardrum out — I don’t even know how that happens," Shelton told “Entertainment Tonight.”

"I don’t know how it heals either,” he added. “But, she says she can hear now. She’ll be all right."

To answer some of Shelton's questions, we talked to Vijay Mukhija, MD, an ear, nose, and throat physician and facial plastics surgeon at ENT and Allergy Associates in Melville, New York. Here, he explains why eardrums rupture, what it feels like, and what to do if it happens to you.

It’s exactly what you might think: Pressure builds up on the eardrum and eventually causes it to burst, Mukhija explained. “The eardrum is paper thin, so any buildup within can lead to a perforation.”

Our eardrums act as a barrier, protecting the middle ear. So when there's a hole, water and debris can reach the middle ear, potentially causing infection.

The eardrum also acts like an amplifier. “A hole in your eardrum decreases its ability to take a sound and magnify it,” Mukhija said. That's why it's harder to hear when you have a perforated eardrum; and the larger the hole, the greater the hearing loss.

What puts someone at risk for the injury?
Changes in air pressure when you're flying on an airplane can cause a rupture. But more commonly the culprit is an ear infection, Mukhija said. And flying on a plane with an ear infection leads to an even greater risk of an eardrum rupture.

An upper respiratory infection (aka a cold) like the one Stefani had, or a sinus infection raises your chances of having an ear infection. That's why doctors recommend that you avoid flying or scuba diving with any of these infections, Mukhija added.

Using a Q-tip or another object to clean out your ear canal can also puncture the eardrum. (Word of warning: Don’t stick things in your ears.)

RELATED: 5 mistakes you're making cleaning your ears

How do you know if it has happened to you?
You’ll feel pressure followed by a sharp pain and sudden relief from the pressure. “You will also have a discharge of fluid coming out of the ear," says Dr. Mukhija. "It's typically bloody, but can be accompanied by pus.” The oozing may continue for up to five minutes. You’ll also experience some hearing loss.

What should you do?
See your doctor. "The great thing is that most ruptured eardrums heal spontaneously," Mukhija said. "But we like to see patients as soon as it happens to treat the underlying problem." (For instance, if you have an ear infection, you may need antibiotics.) An MD will also clean out your ear canal, and send you home with instructions on how to care for your ear at home — such as keeping it as dry as possible so water doesn't contaminate the ear canal. Your doctor may also give you a hearing test.

While the pain may only last a few days, the hearing loss will persist until your eardrum has fully healed. If it hasn’t patched itself up in three months, your doctor might be able to repair it with an in-office procedure or surgery.

This article originally appeared on Health.com.