Advice Please

Rebecca • Im 22 years old, been diagnosed with possible Polycystic Ovary Syndrome. Suffer with low vitamin D. Been trying to conceive for over a year.
Well AF still has not come, it was suppose to come on sunday its now tuesday and still no show of AF. Still getting light spotting but noticing it when i go and wipe. I have PCOS so its normal that I dont get periods sometimes. But been feeling dizzy and sick for the last 2 nights. What could it be? Could I still b having implantation bleeding?