TMI Question (no pix) is it possible to ovulate during your period?

Sarah • TTC baby #1 since October 2014
TMI sorry I'm just curious but I always try to track my CM and most of my cycle its dry or sticky never really that fertile egg white\clear CM that they say is best for getting pregnant so today AF showed up, on time and when I went to change my tampon and I was wiping there was this clear watery looking CM!! So now its got me wondering if its possible to ovulate during AF my SO and I would never BD during AF I don't think either of us would be able to do it can't like a round of BC change my cycle? Make it more normal? Please help!!!!