Not pregnant and period is very late

I am stressing out a lot. I am about 10 days late. Last time I had unprotected sex was Oct. 23rd and before that was Oct. 14th. Oct 23rd was the week my period was supposed to come and it didn’t. I took a pregnancy test this Saturday and it came out negative. On Oct. 10th I had an endoscopy and they did blood work for pregnancy and that was negative.

It says to wait at least two weeks after sex to get an accurate reading.

I am freaking out bc I don’t know why I haven’t gotten my period. Anyone has an idea of what could be happening.?!