Hi ladies, I wondered if anyone has been in the same situation before?

So I usually have a 26/27 day cycle but this time I was 3 days late with symptoms such as nausea, fatigue and major hot flashes. I tested and kept getting negatives. Cycle day 30 I started spotting then the day after I had a light/ medium bleed like a period. Following day spotting again. Then today I started feeling really light headed, dizzy and fatigued. Did a cheapo test and it was a vfl. Tested using clear blue digital which showed not pregnant. Could this be a chemical?