From what I've read, ADHD can cause the problems that you describe. ADHD, like autism, is not a simple disorder and it manifests in different ways. So it's hard to say if your issues can't be explained through your previous diagnosis.
Regarding autism, while no one here can tell you whether you have it or not, we can tell you about how it's recognized and diagnosed. Autism isn't limited to social difficulties, and a person has to have functional deficits in several areas in order to be considered for a diagnosis. Those areas include social communication and interaction, as well as restrictive or repetitive patterns of behavior. The latter manifests as stimming, need for routine, restricted fixations, and sensory dysfunction. According to the DSM-5, your symptoms have to be clinically significant, impairing your range of function to an extent, in order to for you to be considered "autistic."
I hope that helps and that you get the accommodations/treatment that you need. Good luck.
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I have not the kind affections of a pigeon. - Ralph Waldo Emerson