10 dpo - being a silly goose

Hi guys. This community is fast becoming the one place I find some hope. I'm 10dpo today. Sharing my chart which I thought was all okay, until I realized last month my temps all stayed above coverline and yet I got AF on the expected date.

For some reason my temps during AF are pretty high. I wonder if I'm doing something wrong while temping. I do it rectally which is supposed to be accurate? Same time too. No activity before temping.

Been testing 7-8-9 dpo and again this morning. All neg. Bleh.