Period 2 weeks late, brown spotting and small blood clots?

Anonymous
Period related question. If it grosses you out, please don't read ahead.
I'm l4 days for my period (it's recently gone super irregular like this). I'm now sort of spotting? It's very light, and the colour is a light brown? And I am getting small blood clots with it.
It's not a period. I don't know what to consider it or what it is. I know brown blood (even if the colour is light and the flow is light) it's considered old blood. However recently this keeps happening before the start of my period (and the period is always coming late now)? Does anyone know what's going on? And why am I passing blood clots now?
I also did an ultrasound which said I had an antral ring of follicles suggestive of multifollicular to polycystic ovaries. My gynaecologist said it not as common for PCOS to randomly occur. I am 18. I have had regular periods all the time. I started my period at the age of 10. I have to do a blood test on the second day of my period, but it hasn't even started yet. Please help? Also I'm a virgin, so zero chances of being pregnant
Period 2 weeks late, brown spotting and small blood clots?
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