Hello,
Irregular periods are common in menarche or menopause. Hormonal imbalance is one of the causes of irregular periods. The other cause of irregular periods could be due to hormonal imbalance, stress, chronic illness, polycystic ovarian disease, thyroid gland disorders or diseases, pituitary gland tumors or cyst, galactorrhea, prolactinomas etc. You should consult a gynecologist and get examined and investigated as soon as possible if you are having irregular periods.
I hope it helps. It is very difficult to precisely confirm a diagnosis without examination and investigations and the answer is based on the medical information provided. For exact diagnosis, you are requested to consult your doctor. I sincerely hope that helps. Take care and please do keep me posted on how you are doing.
However, if you're still young like 11 or something then your period isn't going to be exactly normal until your at least 14 but I still advise a visit to your doctor. :)
It depends on your age but if you're at least 14 and up then this isn't normal. If that is not your age, I suggest you go get checked out by your doctor :)