You are suffering from irregular period and there are several reasons to be ruled out before taking any type of birth control pill. These include hormonal
imbalance, uterine pathology, stress/anxiety
problem, wt gain/ extreme loss, irregular eating habits etc.
Therefore, I suggest to consult with gynecologist for relevant investigation like USG abdomen and other hormone assay etc. After that, you can take hormonal pill to regularize your period. Also, you need to inform your parents regarding this.
Avoid stress, take healthy diet with Vitamin & iron supplements
, control body wt and need proper sleeping.