I've always had a hard time fitting in and making friends. I've never really understood why, but now I think I know why. I've begun to notice I'm not as skilled when it comes to social interaction as my peers. I feel dumb at times because they know exactly what to do and how to respond etc in a conversation and I just don't most of the time. It feels like everyone got some sort of in-depth manual on how to interact with other people and I didn't. I didn't realize how socially awkward and at times rude I was until my parents pointed out to me things I did like not using any body language, not responding to some peoples' questions, talking too quietly and a few other things.

I have problems outside of social awkwardness, too. I am sensitive to loud noises, spicy food, and I cannot bring myself to eat jelly-like or slimy food textures. I also have a limited set of interests, like only 3 t.v. shows, I visit few websites, a small amount of video games and books, and I have a hard time adopting new interests. I also have a hard time doing things spontaneously; whenever my dad's gf tries to get me into a new show or movie I can only agree to watch it if she tells me a few days before she actually plans on showing me. I have a hard time going to big events if my parents tell me the day of, it makes me really uncomfortable and I have to know a few days before.
Does this sound like autism? I've done research on so many websites (mental health and autism organization sites, not just a few sketchy sites or blogs) and took a few online tests and all of that has led to strongly believe I am autistic. I really want to go to a professional to get a diagnosis. What are your thoughts?