Missed period but negative pregnancy tests

I’ve missed my period for the first time in all 9 years I’ve had one. It’s over a week late, and that only happens in July because of my trauma from a few years ago. But it’s April. Been sexually active and pretty safe, too. Nothing abnormal.

Took a test at 5 days late. Negative.

Took a test at 7 days late. Negative.

No symptoms of pregnancy. All PMS symptoms disappeared. Clear discharge like I’m about to ovulate. Today a few cramps like PMS but nothing I’ve never felt before. I’m so confused and concerned.

Thoughts? Advice?