How do I explain this to my dad

Hello, I'm a sixteen yo girl who have suspicions of autism for a year now, I never saw a psychiatrist even though I want to, to be sure of my suspicions but I have a hard time explaining it to my parents because I'm scared they'll see that as creating problem or victimizing myself. I was always considered as a intelligent and mature child so it would be difficult for them to understand that their daughter might be disabled. But since I'm a teen I had a really hard time dealing with sensations and social interaction, one day I made research on autism just to win an argument against my step dad (who doesn't believe in mental health) and I found myself strangely understood and relating to the characteristics. Since then I made thorough research on it and I'm seriously recognising myself in it. I don't know if I seriously am autistic but I just want my parents to take this seriously and help me even if the result in negative in the end.

Recently I had what I think is a shutdown in front of my father. For the context I spent 10 days seeing people everyday with event that took my energy so this day was THE day I could stay at home doing nothing. But when he came home he was not made seeing that neither me or my siblings did something in the house. The atmosphere quickly became stressful and I tried to focus on doing things but I would block on which type of glass I should put on the table and my stims would intensifies. I couldn't move normally my body and mind would sort of block the lights and noises were all too much and I couldn't speak. The problem is that I didn't want my father to notice and I ended up crying when he asked me a question. I went to a place with no light or people and he couldn't understand my behaviour. He knew that it wasn't the first time it happened to me (It already happened with my mother but it was more intense) and called it a epileptic seizure.

Now I know we're gonna have a discussion on it and I know I should be more honest with him and try to explain it what I think it is but I don't want him to think that I'm doing that on purpose or that it's fake. I'm very scared of his judgement and the way he'll see me if I break the image of the perfect daughter who always have control on everything whether it's her grades, schools and social life. I'm scared of telling him that I'm not okay and that I may need help. I wish my true self would be enough to not disappoint. I want to find the good words to be the more understood possible but my thoughts are a mess and I'm scared of not putting the good words on what I feel. PS: Sorry for spelling mistake English isn't my first language.