PCOS  consists of a number of symptoms irregular periods,   signs of increased androgens - excessive body hair growth,  darkening of skin at certain points etc & polycystic ovaries on usg. Out of so many features 2 features need to be fulfilled for diagnosis. If you're having cysts in usg you should have other features along with period problem to be diagnosed PCOS.  If not irregular periods for past 2 months can  be due to an anovulation  ( eggs not being released during that cycle) . If  problem persists need to see a doctor.