I'm a virgin, but i've missed a period. i had amenorrhea for three years before i got it back a year ago. is this a cause for concern? or is it normal

Irregular period: There are several reasons to have irregular periods. Mostly due to an imbalance of hormones in your body. When a girl starts her period, the cycle hormones are usually not fully established. It can take about 3-4 years for this to happen. I sounds like you had your first period at least 3 years ago. Therefore, you probably have a hormone imbalance that should be check by a doctor.