Hey did i start my period?

Hey i woke up and go to the bathroom i was 2 tired 2 luk down but then later on when i go 2 change 2 go 2 the store i found this brown stuff in my underware idk what it was so i change it... it was all gooey i must have gotten it over night idk what it was but it was alot (not rlly) but it showed on both sides of the underware soo..... idk cn u help me thanks!