I got fired for stuttering to a customer. 😑

I got fired for stuttering to a customer. 😑 I would understand if it affected my job performance, but I'm not even in customer service or anything like that. I work part-time as a janitor and a customer asked me where something was. I stuttered my way through the conversation and I could tell he was getting uncomfortable. he spoke slowly to me like I was mentally challenged and said, "It's okay dear. I'll find it eventually, ooohhhkaaayyy?" This kind of irked me but I just smiled and nodded as he backed away. I was later called into my supervisors office and I saw the manager there. They told me if I enjoyed my job and said that unfortunately my performance left customers uncomfortable in the store and will contact me when there is another position available. Basically I got fired for stuttering. I got escorted out with angry tears in my eyes and everyone was looking at me wondering what happened. What can I do to get my job back? Update: I took you guy's advice and talked to my dad about what happened. Hee agrees with seeking legal advice. Thanks for the help and I'll update later to see how it goes.