Period????????????? :(?

ok well i was at school and i went to the bathroom cuz i needed to go! lol and also it was a lil itchy down there ya know so i pull down my pants and i see this brownish sticky gross stuff on my underwear but i couldnt really see the color that much cuz i was wearin red underwear what is this cuz once i was told this is a sign of startin your period but im only 11?? help please