With PCOS you have very irregular cycles which is what prompts most women to go get diagnosed. And with that not every month a woman with PCOS will ovulate but i know myself personally when i do ovulate some months are unbearable as you mention. Same as when i do happen to have a period the period pains are excruiating as well other symptoms are heightened, so instead of light nausea i can vomit, extreme moodiness and very sore boobs.

I suggest speaking to your GP. PCOS can be detected through a simple blood test.