Can anyone help me interpret my BBT chart? This is my first time temping, and I’m making sure to do it at the same time every day as soon as I wake up.

My cycles are typically 42-45 days with O around day 29, but some months I don’t O at all. This month looks like I ovulated on day 40. I had a dip yesterday and another rose today. Can anyone tell if I for sure ovulated or what this recent dip and spike mean?? Any insight at all would be greatly appreciated! We’ve been trying for a few years.