Age Discrimination?

I was terminated from my position as an administrative assistant two weeks before I turned 50. I had worked there 6 1/2 years. The "reason" was that my job was changing and I did not have the "skills" to change with it. I had been an admin assistant/receptionist/secretary for over 24 years at that time and my skills were up to date. They did not tell my HOW the job was changing. I later learned they hired 2 younger women in clerical positions. Did I have legal recourse to sue for discrimination?