Thats a pretty well made out list there!
my honest opinion is that it seems a lot of it is "like" that, but not exactly what happens. there could also be other causes. and any meds you might be on could be affecting or masking some things. im not saying that you arent, and im not in any way someone who can diagnose anything. meltdowns can be precieved as fits by the people looking on the outside, because they appear to be showing anger. but its not anger associated. its when the brain has too much stimuli on the senses where it has a meltdown and they are usually not something with where the person is able to be alert(conciously able to plan or think or problem solve) until after the meltdown.
its a really great gift that youre able to know exactly what you want to say when writting it. (i struggle a lot with that. its all there.. but stuck.. i think in pictures. words are only a foreign language that i constantly have to interpret to understand. and often i cant explain what im trying to, and i get frustrated at myself. people on the outside think im great with words and explaining things... but im not. and i havent been able to explain why im not.. which in itself is me showing that im not great at expressing myself.. but they tend to think that them stating how well im expressing myself and trying to counteract/void what i said, they think after saying that, it ends with that... the fact is, it just begins with that. )

im primarily thinking of classic autism when im referring to "my honest opinion" , i know very little about PDD-NOS, and where those who lost the diagnosis in this past dsm book change- where they went on the diagnosis, as the book mentions those that no longer meet the criteria will meet a different criteria (but ive not found what that moved to). any meds can also mask or alter your symptoms on the spectrum.

and as its a spectrum, not one person is identical, so its super hard even giving a personal opinion on it, because i dont want to discourage you. in the end, its how these things affect you, and if the care that can be given to those on the spectrum will greatly benefit you and is desperetly needed and seeked by you, then youre probably "spot on" about you being autistic.