PCOS - 8 days or 26 days late, but negative tests

Hi all, I need your help! I am trying to concieve, but have PCOS. My period is late, my boobs are sore, I keep getting nauseus, my food tastes have changed (like stuff I never did, not keen on eating stuff I usually have every day). Now, my period is 26 days late, but I did get a bit of spotting (don’t think it was a period as no other signs of period with it). Even if I do count the spotting as a period, I am still 8 days late. pregnancy tests keep comjng back as negative. I even went to see my general practitioner doctor and they didn’t think I am pregnant. I am freaked out as I had cysts is the past (biggest one spanning 18cm!). I really want this to be a pregnancy. Does anyone have similar experiences? Did anyone else test negative for pregnancy even though pregnant? Any advice would be greatly appreciated.