Singer Fergie was so paranoid during her drug using days, she became convinced the Federal Bureau of Investigation (FBI) was stalking her. The Black Eyed Peas star has been sober for years, after winning her battle with crystal methamphetamines. But she tells Marie Claire magazine of the mental effects the drug had on her: "I had about 20 different conspiracy theories. I painted the windows in my apartment black so 'they' couldn't see in. "One day, when I was about 90 pounds, a guy comes up to me... I'm searching in the bushes for clues about whatever they're after me for. I'm in a cowboy hat and red lips. He hands me a muffin. I'm thinking, he's in on it."