Lady Gaga -- SMACKED in the Head by Giant Pole During Show

Lady Gaga got into a bad romance on stage in New Zealand ... with a giant pole that fell on her head!

Gaga was performing her song "Judas" when the mishap occured, but she never missed a beat.

Later in the show, she told the crowd, "I want to apologize. I did hit my head and I think I may have a concussion. But don’t you worry, I will finish this show."