Can someone help🤞🏼

So I’m currently 4 days late on my period. I did have sex around and on my ovulation week but I didn’t get a positive ovulation test but I read that people with pcos can rely on ovulation test. My periods are always normal and I was supposed to go to the doctor on Monday for some medicine to help with ovulation. I’ve taken tests but they are negative but I have no symptoms of my period coming. Just been really dizzy and nauseous the last few days. And also with both my sisters they didn’t make enough hcg for a urine test to show positive. My little sister wasn’t able to get a positive test until she was already 4 months. I’m just wondering if there’s a possibility I’m pregnant or does anyone have any ideas and what could be throwing me off?