Dick,
Did you per chance record video footage of your son's performance this past weekend? As Rick stated it is okay to record your own kid's matches and actions no matter what the results. You might be able to learn something from the video.
You may believe that I am the wrong end of a mule but at least I am true to my word, not a backstabbing, two-faced arrogant, overly opinionated, fecal matter stirrer.