What Is The Cause For Prolonged Periods?

sir, i have irregular periods...i have period duration of 40 days when i startedmy mensturation.after that the period duration increased and reached upto 7 months.i have scanned my utreus and found pco.i consumed metformine tablets for 4 monthsm and found no cure. then i go for hormone test and my prolactin level found 35ng/ml.then consumed cabgolin .5 for 1 month then .25 for 2 months.now level is 30ng/ml.and ma periods appearing between 37 days but have stomach ache before 5 days of period...is there any problem