Help! How long is too long?

My period is 12 days late, past cycle day 28

All negative pregnancy tests.( most recent yesterday fmu)

No new routines or increase in stress.

My cycles have always been every 26-28 days

Rarely I have been a day or two late but very unlikely.

I want to call the doctors, buy they said to wait 2 weeks before calling.

Close enough, right?

What would you do?

The only way I have ever been more than a day or 2 late is if I was pregnant, but with tests being negative things are looking more

Complicated.

(LMP September 14)