It is not normal. Do urine pregnancy test If you are sexually active. If no then take castor oil 50 ml in morning with hot water and you will get loose motions on the same day and periods within a week. Once in a while you can get irregular menses because of hormonal disturbance. But you have irregular cycles then you should do Thyroid function test and serum prolactin fasting and CBC BLOOD SUGAR LEVELS. Do ultrasound pelvis. Consult ayurvedic gynecologist for detoxification Panchakarma treatment and ayurvedic medicines with modification in diet and lifestyle which will repair metabolism and regularise your cycles.