Rapist or imagination

I think I saw my rapist! I'm not sure tho. I was raped at 15 I'm 30 now. This man looks identical to the image of him in my head. I only saw my rapist once in my life. How will I ever know if it's really him or not? I do not want to frown at someone that could possibly be innocent but each time this guy comes through the door at my job a bubble comes into my stomach. What should I do? Rape went unreported because he and his friends found my family members numbers and harassed them threatening to kill us all if we talked and he threatened to shoot me the night of my rape if I ran although he beat me while raping me. Told me to call him Mr magnificent. I hate what he did to me. And I want to confront him. How can I know if it's him? Should I say Mr. Magnificent is that you from 15 years ago? Lol my nerves are bad each time I see him. I get this sharp pain in my stomach