PP& BC

I've posted SO many times lately about literally the same thing. But earlier in the week I finally went to planned parenthood just to get tested/pregnancy test/birth control. My period is 28 days late, 20 freaking 8. I took 4 at home tests which all came back negative, they did one there, negative. I'm just so confused 😂 my period is always very normal or only late by a week or so. Any ideas or advice would be great