BBT Chart.. Help!

Anna • 31. Married. Mother to DD after TTC 3 years. Have been TTC #2 for over 6 years now.
​Can someone please help me figure it out? I had one pos opk but I only test in the evening so I can't figure out if it caught my LH on it's way up or after I ovulated. I don't even know when I ovulated. Also, trying to figure out if my luteal phase is too short :/ my last cycle was long(ish) at 31 days.