Question 2 pics

Jamiya
I've been using glow for just about 4 weeks. I was in the pill and had a 28 day cycle. Before the pill, they were every 34 days. As I understand it, when ovulation happens the body temp spikes. However, during glow's predicted fertile time, my temp didn't spike but my temp is spiking now...a few days before glow says I'm supposed to start my cycle...ideas ladies?