Feeling guilty and bad of asking for help

My experience with mental health professionals over years has been negative. Even the recent one hurt me by saying “yeah, you have a lot of autistic traits, but now it’s so popular and trendy to be autistic, everyone wants to be autistic” this one really hurt me. I experienced so much trauma, it’s actually a miracle that I’m still alive. And I share my experience, I trust someone and hope for help, but get this instead. She made me really refuse even trying to get the diagnosis, because it’s “trendy”. I’m not sure if it’s the effect of social media trends or what, but it was humiliating and looks like these words themselves triggered some trauma in me. That professional also said, that it’s not an issue I have no friends. Not everyone must be popular. Recently I had a situation with a dermatologist. I waited 1,5 hour in the doorway, sitting on a chair. The whole time there was the awful squeak and crash of slamming doors. Plus swoosh of conversations, elevators plus everything around. It didn’t seem to bother anyone but me. It gradually made me feel crazy, overwhelmed headache head spinning and just awful. This feeling is absolutely familiar to me and I know well what helps me avoid crying and having meltdown due to sensory overload. To soothe I started rocking and tapping my fingers. People who sat next to me moved their chairs to not sit next to the freak. When my turn came and I was called to the doctors office, he examined the tumour and decided it had to be removed, but then he also said that I have mental health issues. He mentioned me being nervous and not looking him in the eyes. I explained what made me upset then he said I must have some phobias. He advised me to go to the emergency room and seek a psychiatrist. I went there, the lady looked at me like I was crazy and she said they have no psychiatrist, I have to look in other houses of this huge medical complex. There were a lot of houses I asked few other people where is the psychiatrist, but apparently nobody knew. The staff not knowing where is a psychiatrist in the hospital… well ok. I finally found a house with written “mental health” so I entered and there I found out that for emergencies I need to go to emergency room. I had impression that nobody wanted to deal with me and everyone thought of me like I’m crazy so it’s better to get rid of me. Now I fear I will be treated same by another specialist. I got suggestions at work that I should be under the psychologist assistance. I often feel low and not worthy, guilty, worse then others. Sorry for long post. Does anyone know how to approach a psychologist to not be treated like you are exaggerating and how to recognize if the specialist is actually good? Or maybe it’s better to stay away from them?