I guess by 9mm you are referring to the follicle size in your ovaries. Usually in a ovary follicles of about 20 mm are produced before ovulation, so 9mm is OK!!!
If you have PCOD is not a life threatening disease and it is a lifestyle disease where hormone disturbance causes many changes like weight gain, increased facial hair, anovulation, pigmentation on neck, etc
As per data given by you, at height of 5.3 feet, your weight of 75 is too high. You need to be around 55, so this 20 kg weight has to be reduced, to get better control of your pcod.
Hit the Gym, do cardiovascular exercises under supervision
Meet a dietitian, and plan a healthy nutritious diet with low cal foods to help prevent cravings, as you lose weight
Irregular menses will become regular as soon as you lose weight, on its own.
But if they persist you can take help of a Gynecologist who can give you medicines after doing basic hormone tests and ruling out
thyroid problems
As compared to scanty flow, heavy flow is BAD, and it needs to be dealt with medicines as it reduces your hemoglobin.
so get a gynec consultation and take medicines for preventing heavy bleeding when it happens withing 1st day of menses