Your chart's kind of hard to tell because you didn't have many points before O. Usually, based on the points before O, FF will give you a baseline temp like if you are >= baseline then you are in the second part of the biphasic; if you are <=baseline then you're probably bleeding or about to bleed.
Reading charts it's all about looking at the patterns over time, rather than any individual temperature. My chart in my signature shows that my baseline is at 97.9 right now, and before O I had some 97.9 temps after O, I also had a couple of 97.9, but it was mostly 98.0 or above so that's what biphasic means. Like in math class, if you graph out all the points, and you had to draw just one flat horizontal line in between lower temps and higher temps, you should see majority of points before O under that line, and majority of points after O above that line.
But because you are missing a lot of data points before O, you can't draw the line right now. But your CM and OPK signs all say that you probably O'ed. So just keep temping next cycle and you'll get the hang of it