After scoring critical acclaim with her 2010 indie film “Tiny Funiture,” Lena Dunham has turned her attention to the small screen and her new HBO series “Girls,” which premieres Sunday at 10:30 p.m. Documenting the trials and tribulations of four twentysomething women in New York City, Dunham writes, directs, and stars as the confused but funny Hannah Horvath. Dunham and “Girls” producer Judd Apatow chatted with reporters recently at the Television Critics Association winter press tour.