I am off my period? ?

So i probley had my period 2 or 3 weeks ago and about 3 days after that i had some blood wich came out when i wasent on my period so i dont no what is wrong with me i havent had everdo you think its because its close to the end of the Month should i go to the doctors and tell my mom and idk if this will help but i am 11 i am soo scard plz i feel like crying but plz