What is this I'm going through, PTSD?

I'm getting false backs and recalling memories of my last workplace. I have all these flashbacks where I would walk past people at work and they would give me these dirty looks just for walking past them and making casual eye contact. Sometimes I would try to read a person's face to figure out who they are and I would get dirty looks for that. But I know casual eye contact and reading a person's face is not a crime. These same type of people would make fun of my job too because they were a different industry to me.

However because I got so much negative attention and memories of it, it sometimes makes me feel guilt. But then I realise those people hated me because they didn't find me cool or popular. So I'm feeling guilty and like a horrible person because I was given negative dirty looks since they did not like me.

Over time I would always avoid eye contact with these people because I did not want any negative attention. But then I realise this didn't feel normal. I felt like I was psychologically bullied into being this person who never gets to make normal eye contact so I ended up looking at the floor a lot.