Dollar Tree — discrimination against an employee

I worked part time at this store for several weeks. During this time I had a problem with my foot and I couldn't walk fast. (I later had to have a stint put in my leg). One night right before closing, the manager (Tina I think) told me to clean the bathroom, which I did, but caught me as I was returning to the register and told me that I wasn't walking fast enough and something would have to be done about it. I have to preface this by saying that this store HATES the elderly and especially employees. By elderly I mean 69 years old. They shouldn't have hired me if they thought I was too old. There were always complaints about the manager and cashiers being rude. I did everything they asked me to do but it was quite obvious that they wanted me out of there. I know this will probably go no further than you reading this, but it is not too late for me to go the EEOC.
Thanks,
Joan Layton