Can you tell me is a hormonal imbalance common in puberty?

Please clarify your: question. Girls do not have regular menses till they ovulate. Obesity may be a sign of PCOS, polycystic ovaries, which has related endocrine problems. The age-appropriate task of individuation causes teens to question family values & begin to create their own. A push-pull of seeking independence while needing nurturing & support can lead to conflict, if not seen as a normal developmental stage.

Yes: Puberty itself is a state of hormonal chaos at times. If by hormonal imbalance you mean something beyong normal pubertal changes, yes, it is possible for something like thyroid imbalance, insulin resistance, other hormonal disturbances to occur at ant time in life.