Suggest Treatment For Irregular Periods

hello doctor, I am suffering from irregular periods since they start..7-8 years before they were very painful,,but after that they become smooth..but my periods are continueously irregular..means over a month one week, 2 week and now 2 months& 11 days have passed,bue didn't come.. i am feeling in my own that they are coming as there is light pain below my stomach and around waist..pls suggest me.. i am worried