4 days late, super high cervix, thin milky white cm and a negative pregnancy test?

Hi everyone!

I am 4 days late with my period. This would make it cycle day 33. I ALWAYS fluctuate between 28-30.

There is no sign of Aunt Flo.

I took a pregnancy test yesterday but it was negative.

Today I checked my cervix and it is super high up and has thin milky white discharge.

Is my period starting soon or do I just need to wait longer to get a bfp?

Has this happened to anyone before?