I got diagnosed with high functioning autism today

Hi

i usually don’t talk to people on forums but I felt the need to write down my feelings after today. I don’t know if people will read this but I think it will help putting it out there. 
I’m a female in my 20s and today I was diagnosed with high functioning autism. I didn’t really believe for a moment that it was possible that I had autism. It never occurred to me. I’ve known for most of my life that I was different to other people. People have always known me to be a loner who doesn’t make friends and just likes to stay in her own world. I like solitude and getting lost in my own head. I like to make worlds and live in them instead of living in reality. I always knew that wasn’t what ‘normal’ people do. I was told by my care coordinator who helps me with my mental health that she thought I had autism. It seemed a little ridiculous to me at first,  possibly because I knew very little about autism. I always put my differences with other girls to growing up without a mother. I love video games and books. I like my room to be dark and cold. I like the quiet. I don’t wear makeup and I hardly get my hair cut (mostly because I’d have to talk to the hairdresser ) and I love learning about new things all of the time. My dad usually calls me Spock because of how logical I can be versus emotional. It can be difficult to respond to other people’s feelings. 

Today was nerve racking and sometimes a little painful to face. The lady who diagnosed me was very nice. She had the lights off in the room. My care coordinator helped me while I was there to answer the difficult questions. When I got the diagnosis above everything else I was just angry. I’m angry that it has taken so long to get to this point. I’m angry teachers didn’t pick up on it. I’m angry doctors didn’t pick up on it. I’m angry my dad didn’t pick up on it. Today I got the answer to why I am the way I am and all I can think about is the bullying from school and the jobs I’ve had to quit. I feel let down almost. All of my experiences over the years created mental health issues that I think could have been easier on me if I knew what was really going on. I’m feeling a lot of things right now and I’m worried about the future. I’m going back for a follow up appointment in a few weeks to ask more questions if I have any. 

I guess I’ve been drawn to this forum because I want and need to know that I’m not alone in these feelings of confusion and anger. When I told my family I had high functioning autism today they didn’t seem surprised at all. My brother said it was only a matter of time. I asked why he didn’t tell me I might have autism and he said it didn’t really click until I told him someone else thought I might have it. 
Is autism really not that talked about? Do I need to hide it from people because they might not understand? Now that I’m home I have a lot of questions and I thought talking here might help.

Thank you for reading.