Period won’t start- worried 🙁

I am extremely regular with my periods. I was randomly nauseous on Monday, and my period was due on Wednesday. It is now Saturday, and no sign of period. I tested twice at night on Wednesday, the day of my missed period, and it was negative.

A littleee frustrated. I’m not pregnant, but my period won’t start. I’m worried there might be something wrong with me. I made a doc appt. Monday. I have been having period symptoms - slight cramping and boob pain, yet no period and not pregnant.

A bit worried as I do have health anxiety.