Hello and thank you for approaching DoctorSpring.
In PCOS you have some anovulatory cycles (no ovulation takes place) and some ovulatory (ovulation takes place) cycles. Hence if ovulation does take place during your menstrual cycle and if you have sexual intercourse around the same time IT IS POSSIBLE TO GET PREGNANT even with PCOS (not treated)
Even if you are not taking medications, you will have ovulatory cycles. However cycles are irregular. Hence it is possible to get pregnant if you have PCOS even if you are not on medication.
In your case however it could be that your cycle is delayed as a result of PCOS and your having pre menstrual symptoms. So you can never know. I would suggest this :
(1) You wait for another week, and at the end of that week if you do not get your period, you get a Rapid urine pregnancy kit test done to rule out pregnancy.
(2)IF the test is negative and you still do not get your periods for another week after that, I would suggest you visit your Gynecologist to get your Serum hCG levels and Pelvic ultrasound done.
In some cases the urine pregnancy test can come negative if your ovulation was late and you conceived but as a result of late ovulation your hCG levels have not risen enough to be detected by the pregnancy kit. Hence I would say wait for a week and get your pregnancy test done. It could be that you are experiencing pre menstrual symptoms and will get your periods anytime. )
I hope this has helped. Feel free to follow up.