Am I wrong for not allowing my son's girlfriend over anymore?

My son is 18 and got his first girlfriend. She's 36.... I don't like it but he's legally an adult so I can't stop it. I have no idea what a 36 year old could want with my 18 year old who hasn't even graduated high school yet. Why I don't want her over my house anymore is because she took my son's virginity and will not stop trying to talk to me about what sex with my son is like even though I told her I don't want to hear about that. Even my son gets embarrassed. She will tell me how he always wants to guy since their first time. That he's an animal. That she may end up having his baby soon. Tries to tell me about his size. I blew up on her and said if she can't respect my home and keep the bedroom business to herself then she can't be over here anymore. She told me "Wow. Didn't know you were that boy mom." And laughed at me. I'm 6 years older than her. Am I wrong for finding this woman very disrespectful and not wanting her at my home. It's almost like she fetishes having sex with a teenager and is bragging to me