Final Exams/Graduation First?

I am kind of down because I couldn't go to the UCI stage race in Axel this weekend because one of my end exams was on Friday, and I couldn't make it to the race on time.  I just found out that the Try Outs for the European Champsionships Velodrome are on the same day as my high school graduation.  I am having some bad luck with scheduling this season. My mom is American and insists that school comes first. Doesn't she realize yet that we are living in Europe?