Paris Hilton is putting blood, sweat and tears into her new music video … catching a bloody knee injury on set after her recent catastrophic trailer fire.

The heiress gave a glimpse into her latest challenge shooting the “Bad Bitch Academy” music video … which included a cut to her knee that required medical attention … before filming could resume.

Watch the vid … Paris is seen taking a closer look at her blood-covered knee, asking those on set if there’s glass inside the wound — the foreign object turns out to be a rogue sequin … likely detached from her shimmery silver outfit on the shoot.

Crewmembers encourage Paris to power through the injury, calling her a “trooper” … noting they’ll cover up the cut with makeup, and it won’t be visible in the next shot.

The show must go on … and the socialite agrees, declaring she’s put her all into this music video.

Paris is, of course, referring to her makeup trailer fire in mid-August … which destroyed a number of her designer clothes — including custom Swarovski outfits — purses, jewelry, computers and personal mementos.

TMZ broke the story … Paris was in downtown Los Angeles shooting her new music video when her trailer went up in flames — though, thankfully no one was injured.