The title says it all really, basically I want to write a character with realistic paranoia and PTSD. The basic idea is that because of the fact he saw a friend murdered at the age of 8 he developed an intense fear of masks leading to a fear of mascots as well. The thing is, I have no idea how far to go, at them moment the basic thing is if he notices someone in a mask he'll just silently speed walk away without telling anyone and if one catches him by surprise he'll just sprint to the nearest safe place (bathroom, outside, a nearby shop etc) and refuse to come out until he's been assured the masked person is gone. He will occasionally be struck with nightmares and is very distrusting of strangers. Finally, on some days, he will just be hit with a wave of guilt and depression, confining himself to his room and coming off very standoffish or aloof. Am I doing an okay job? Is there anything more that I can do? I'd really appreciate any tips/help anyone has.