I am 13 and i have brown discharge??????? PLEASE HELP?

i am 13 and i have never had my period. well i dont think i have cause for the past 4-5 days hae been wipeing brown discharge and sometimes a little tiny bit of blood. i am like fully developed. i also 2 times had like 2 or 3 drops of blood or something brown is it my period or should i wait another 28 days and make sure this will happen again?