I think that you may be over-reacting just a little.  So what’s wrong with taking a Friday morning appointment if that is all that suits you.  I think it would be a little too much to ask that a doctor re-organise his/her day to suit the days you work.  After all I’m sure he has other patients as well with their own requirements.    If you are really happy with the way this doctor works with your child, put yourself out a little, maybe you could even change the days you work!