Talking to self and answering back or when angry kids tend to hit there heads against the wall I can go on and on I'm raising a autism teenager

From someone who is autistic, being overwhelmed or underwhelmed by sensory input, (sometimes) rigid food choices due to sensory issues, difficulties in social situations, and stimmong (ex: hand flapping, rocking, flicking fingers, etc.)

The best thing for me personally when I was wondering this was watching a bunch of videos of autistic people on YouTube covering the criteria under the dsm-5 and how they relate to it. They break it down to be more understandable than just reading the criteria and wondering what social emotional reciprocity means.