I was let go over age . I was given a severance pay & not documents involved. Just told me the check would be in my account next day . I am also not being paid for my last week & a half of work . Can they do this ?

I was hired with intentions of a successful position in a dental practice. After working for 4 weeks I was asked how old I was . He assumed I was younger . Instead of continuing to train me (I have 15 yrs experience) he loved me to another position. I did it , but would check in with him every few months and ask why I haven’t moved back into position. He hired two assistants behind me with no experience. Also said a few times in staff meetings & to me that he likes his assistants young . I had a talk with him a couple weeks ago asking for more descriptions of my job , also let him know I was teaching & training new assistants because they didn’t know anything. Which he had no idea because they work with his associate. One week later I was let go for no reason except I didn’t fit . He gave me a small severance. And hasn’t paid me for my last 6 days of work including over time . I never agreed to or signed anything