Justice, Peace or What then?

Yesterday, I was harshly criticized by two people. I suffer from PTSD. I was being supervised over a job I was given which I didn't understand and I was told by my supervisor that I was going to not be good at it. I was told by one clmate that she couldn't eat all day after she was told the same thing. I really didn't expect to be scolded by the second person. They acted very hard. My supervisor and the second person's suggestions were contradictory, so that was frustrating. My supervisor will do this little thing again and again, she said. I didn't cry, but I at one point I wanted to die. It was an awful feeling that came over me in less than a second. I don't cry easily, but the pain made me feel hated, loathed. I let them talk all they wanted and I asked for more suggestions, hoping that I could get it. The more they talked the more I noticed they made excuses for their skills or high praised themselves. I'm a very peaceful person, but others are in pain. How can I find peace?