Shooting pain in left ovary

On the last day of my period this month I started having a shooting pain in what I think is my left ovary. It comes and goes throughout the day. It doesn't make me double over or anything but I've never experienced this before. I'm 31 years old and have normal cycles usually about 26-28 days apart. The only abnormal thing so far is my opks are usually positive by cd13 and they aren't yet. My temps have sort of been all over the place. What do you think this is?