Hello, There are several reason of irregular delayed period like PCOD or ovarian cyst (most common in this context), hormonal imbalance, over wt, stress/ anxiety, irregular diet pattern, psychological factors etc. Here, you need to consult with gynecologist for relevant investigation like pelvic USG scan, complete hormone assay, blood testosterone & prolactin level, blood sugar etc. Take suggestive measures & hormonal medication accordingly. Take low carbohydrate diet, avoid fast food or empty calorie, do moderate to heavy exercise regularly to control body wt, avoid stress & take sound sleep. Be well & stay healthy.