Hi anonymous and thanks for your question.
Irregular periods can be caused by many different things. They are fairly typical in young women and often are due to changes in your body's level of the hormones estrogen and progesterone.
Irregular periods can also be a symptom of an underlying medical condition, for example polycystic ovary disease (PCOS), uterine fibroids, thyroid disease, a reaction to medication and more.
You may want to see your doctor for an overall health checkup and, if a visit to a gynecologist is in order, then see someone different this time, someone who will take your concerns seriously.
You know your body better than anyone else, and your gut is telling you that something is off.
I hope this helps and encourage you to keep on advocating for your own health and seeking the answers you need and deserve.