At your stage moodiness could be seen due to the changing hormones during the menstrual cycle. We all have good and bad sides to us... it depends which one you want to develop more. The more positive things you do, stronger the brain"s nerve tracts for these areas in brain becomes and that becomes your basic personality. Let the bad side be ignored and it's nerve tract will wilt and later diminish. So, being in the right company is very important.
Next Steps
Start a few sessions of counselling with a clinical psychologist