You can tell she is ovulating when you open their enclosure and it looks like they swallowed a small football. There is a very obvious localized swelling at doesn't last very long, but it very noticeable. Once you see it, there is NO mistaking it.
I would have to say that it doesn't look like an ovulation to me.
Here is a pic of an ovulation... http://www.ball-pythons.net/gallery/.../ovulation.jpg