Yes, PCOS can change your periods drastically. Some months you may get a period, or you may go months without one. Please see your gyn to get treated for PCOS. Normally the standard is Metformin and weight loss [if overweight]. They should also do a pelvic ultraswound to see if you have any cysts on your ovaries.
I do have cysts on my ovaries. I think its 12/13 each one they said. I have taken metformin but had to.stop due to depression. Ever since my first period when i was 11 i have had more periods than a girl should. But i find it strange that after 15years of this, its now changed to going 5months without a single one. I still however, get the symptoms i get when im due on. Ie: skin flares up with spots, irritablity, mood swing. Which.usually pass when i come on. So when i get these symptoms niw, they pass. Yet no period