Why Is Britney Upset?

Photogs caught a forlorn-looking Brit out last night, alone. Upon closer inspection, we noticed she has a cut on her chin - did Britney get into a fight? Quite upset, our girl Brit chose not to spend the night at home...course with all the recent pregnancy rumors swirling around, you can't blame her for getting a little down, but we think there's more to the story than that...details coming soon!