Welcome to HealthcareMagic. From the symptoms oligomenorrhea
is an important possibility. It is infrequent or occasional very light periods. It could be due disease of thyroid gland like thyrotoxicosis
imbalance, pcos (cyst in ovary) or benign tumors in pituitary etc.
I suggest you to get it examined from a gynecologist and get a thyroid profile, hormonal studies and ultrasound
Hope it helps. Regards.