How possible is it for a kid to be incorrectly diagnosed as autistic?

[Rangel7]

I don't really know how to explain my problem in the few words the tittle allows, but I'm concerned about my stepson. He was diagnosed with Autism as a child, yet now he's 19 and I really have lots of doubts about his diagnosis. We don't really have the means to pay for therapy or evaluation, but I'm worried about his mental health. I think we're not helping him right now, but I don't really know how to do it.
I'm sure he looses touch with reality, and I see him sink more and more in his fantasy world. He's obsessed with video games and a particular character/universe from one of his games. He seems to believe that the heroes and villains of the game really inhabit a parallel dimension and that's possible they will show up in ours. Unfortunately that's the only thing he talks about, it's very difficult engaging him for a few minutes in other topic of conversation, and somehow he always finds a way to start talking about those characters again.
I started worrying about this when he insisted he had to take brass knuckles to his graduation ceremony, in case the evil robot of the game (and his creator) appeared in the ceremony. I was able to convince him not to take them, but I'm sure he didn't even understand my reasoning. He seems to think that the characters will pop up in our world at any moment, and he also tends to mix up that situation with religious imagery, so at some point apparently God in his greatness created more than one dimension, hence his "heroes" and Jesus are somewhat related.

Anybody has ever hear of something like this before? Anybody can point me in the right direction as to what material I could read? Please. I'm desperate.

PS: He also has another fixation. He thinks he has some kind of superpower, that he's very strong and something like the "Hulk" (sorry, I don't know how to explain it) He thinks he has to control his temper or his superhuman strength is gonna come out or something like that. He wants to punch or smash things all the time. He also tends to bang things with something is not to his liking. I don't know how to help him

 

[Ereth]

I'm not a doctor, so I can't say whether your stepson's diagnosis is correct, but it does sound like he could have something else going on (such as a condition whose symptoms include delusions), and autism is known to be potentially comorbid with other things.

No matter what the underlying issue may be, he should see a professional as soon as possible, in my opinion.

 

[Saragrl]

Curious? Was he bullied a lot, or without friends? Fantasy thinking seems to be a trait to some people with autism. Since he only believes these people can cross over this world and does not actually see them, makes me think it's not delusion. I had a similar phase in my teens as well. In retrospect I think I was likethat not because I was delusional, but because I was so alone and these fantasies made me feel special in my wold. If they some how became reality I would be special in the real world as well. My therapist said it was disassociation. Disassociation is a subconscious coping mechanism that can become a very serious issue if a person is not able to cope in other ways.

Like Ereth said, a professional is needed in this situation. I don't think any amount of telling him it's not real is going to help at all. If it is disassociation, it is from an internalization of a lot stress and pain. He needs to sort that out with a professional, the sooner the better.

 

[Ereth]

You don't necessarily have to see something from a fantasy world to firmly believe it's real----so this is in fact a case of delusion. I mean, this young man tried to take brass knuckles to his graduation because he believed an evil robot from a video game would make an appearance. If that doesn't fall into the "bizarre" category of delusions, I don't know what does.

 

[Saragrl]

I did not think of it that way. I see your point. Though he should not jump to conclusions that it's something like schizophrenia. Only a doctor will know for sure.