Mood swings are very common, especially during puberty and menopause. In general, eat a healthy diet high in antioxidants and low in unhealthy fats, get your sleep, exercise - and manage stress through meditation, deep breathing, journaling, etc.
Here are a couple of sites that discuss tips, including other ideas like herbs and massage.
http://www.womenshealthmag.com/health/natural-pms-cures
https://womeninbalance.org/symptoms-solutions/irritability-mood-swings/
