no period?

i will try to keep the facts brief and easy.

- stage 4 endometriosis (all reproductive organs, bowel and diaphragm)
- according to the flo app my predicted ovulation date was 21st august, i had unprotected sex with my partner on the 21st, 22nd and 23rd of august
- my period was predicted to start on the 5th september, and i am no currently 7 days late
- i have never missed a period in my life and always had regular averaged period lengths
- i have NO pain??? that’s the biggest thing for me, my pain lasts 5 days before my period all the way to 2 days after ovulation. so around 3 weeks of the month i take pain relief every 4 hours daily. yet??? no period and no pain
- i’ve had 5 negative tests, taken ranging from day of missed period up until today
- i also had a cold start 4 days before my suspected period

so if the negative tests are true, what the hell is going on?