As Fashion Week approaches, not only do designers feel the pressure as deadlines loom but their dogs do, too. Thakoon Panichgul, whose colorful printed dresses have been worn by First Lady Michelle Obama, Sarah Jessica Parker and Rachel Bilson, is prepping his latest collection, to be unveiled Feb. 13, at his Lafayette Street studio. Staffers there were overheard grumbling that Stevie, the designer’s Yorkshire terrier-Chihuahua mix, has become quite snappy of late. There was even an unverified rumor that the dog bit one of the brand’s interns on the backside. Stevie is affectionately named after singer Stevie Nicks, and sources say the pooch is the apple of Panichgul’s eye. At one recent Fashion Week presentation, staffers working backstage even wore buttons with Stevie’s picture. A rep for Thakoon said the story was “totally untrue.”