Get another doctor - if you ahve a cyst that big on your ovary, in pain, and he gave you birth control for that there is something wrong. If you have pressure on your bladder too - there is something going on. GET ANOTHER DOCTOR - get a pelvic abdominal sonogram or cat scan and
get a CA125 blood test to check for ovarian cancer. Get a copy of your reportso from these tests. Go to your primary or even an internist for help but definitely get another opinion.
you will probably need an ultrasound or MRI is see if the cyst has changed.