Might this be age discrimination?

If the younger employee had duties the same or very similar to yours, there is the possibility of raising an age discrimination claim, unless you signed a waiver in exchange for severance pay. The law requires that such a waiver be given with certain safeguards in order to be valid, such as sufficient time to consider the offer, recommendation that you consult an attorney, and the ability to withdraw acceptance within a set period of time. The United States Equal Employment Opportunity Commission office in Houston can consider your situation and might give you some advice. It is your right to file a formal charge of discrimination, whether or not the EEOC intake person believes there was discrimination. Depending on your financial circumstances, you also might be able to obtain advice, and maybe representation, without charge from the Houston Volunteer Lawyers. The Houston Bar Association, number listed in the telephone directory, can refer you to that organization.