Besides the symptoms you’ve described, irregular periods are one of the other hallmark signs of PCOS.
In Singapore, PCOS is most commonly managed and followed up annually by gynaecologists, as there are some associated risks with PCOS, such as diabetes and heart disease.
Because the diagnosis of PCOS requires a couple of bloods tests (looking at your hormone levels) and an ultrasound scan (to look for cysts in your ovary), gynaes are typically the ones who perform the ultrasound scan to confirm PCOS (some polyclinics in Singapore have that capability as well to confirm or rule out the diagnosis before referring you on).
In your case however, it may be worth while seeing a GP or polyclinic doctor first, who can screen if PCOS is indeed likely from your history/menstruation cycle, and then refer you on if necessary.
Skipping straight to see your gynae is certainly an option too if you are in a hurry to get PCOS diagnosed or ruled out.