When did I ovulate?

C.
I think that I ovulated earlier than Glow says I did. I had a backache on day 13 and some pretty intense cramping (right ovary) on day 15 and 16. This leads me to believe that I ovulated on day 15. From what I know about tracking BBT my temps seem to confirm this (steady rising temps). I'm pretty new at this though, so I'd love some opinions from some more experienced ladies! Am I correct in thinking I ovulated on day 15?