BRITNEY Spears is a “hot mess” who needs to “stay home with her kids,” L.A. spies say. Over the weekend, the scantily clad pop tart not only flashed her panties at paparazzi but also let her sundress slip several times, baring her nipples to the cameras. On Saturday night, Spears went to a bar, Lola’s, where she and two friends downed martinis “like water” and partied till the wee hours. Spears’ frustrated rep has decided to take a “hiatus” but generously declined comment on her behalf.