Learning you have autism spectrum disorder can be a very paradigm shifting experience, at least it was for me.
There is no medication to treat the core symptoms of autism. Some people take Risperdal or Abilify which are FDA approved for "irritability or self-harm associated with autism" but I have never had nor wanted to do that. In college in 2012, my ADHD diagnosis was taken away and I was given a diagnosis of Asperger's syndrome (a term that is no longer used for diagnosis, but I haven't been diagnosed under the new system that went into place(in the US) a year later in 2013). What problems are you having? They would need to be treated on a symptom-by-symptom basis. There isn't really a global treatment for it. It is just a different neurology. My most problematic symptoms are lack of social tact and significant OCD/anxiety. I use masking for the first when it would be beneficial for me but haven't figured out the second yet. My anxiety has always been pretty bad. I am on some klonopin, but long term treatment with benzodiazepines is controversial. I used to drink a lot to address the anxiety and to reduce overstimulation but then I had repeated attacks of alcoholic pancreatitis and can no longer safely drink. I feel like the effects of a bit of alcohol made it easier to mask. Masking is basically figuring out how people work and then deciding if you want to imitate that group in a specific situation or not. What do you mean by supports in place growing up? You probably didn't need extensive supports because you only have level 1 ASD (basically Asperger's), which often isn't associated with developmental delays. It sounds like you worked on issues with a psychologist and that counts as a mild support. It is the people with level 2 or level 3 who experience significant developmental delays and generally require the type of help culturally associated with autism diagnosis. Some people don't like levels, but they absolutely are useful for classifying people by the type of support that they will benefit from. Level 1 is a different life than a level 2, which is a different sort of life than level 3. Here is the DSM V definition of autism and the breakdown of the different levels:
https://www.cdc.gov/ncbddd/autism/hcp-dsm.html
You said you were diagnosed with BPD. Do you experience episodes of intense frustration/aka "meltdowns"? Those are a symptom of autism. Sometimes self harm is involved in these meltdowns or overloads. Being female+having those specific autism symptoms could have resulted in a misdiagnosis of BPD. I would bet money that your gender had a lot to do with you being misdiagnosed as BPD.
The old system used to refer to ASDs as Pervasive Developmental Disorders (PDDs) and there were 5:
Autistic Disorder, Asperger's Disorder, Childhood Disintegrative Disorder (autism with apparent severe regression), Rett Syndrome (no longer part of ASD....determined to be a very rare genetic condition affecting females), and a catch-all-others term called PDD-NOS (PDD-Not otherwise specified). All are now diagnosed as ASD except for Rett Syndrome. And autism is now "Autism Spectrum Disorder" and not "Autistic Disorder". Autistic disorder in the old system was more specific and was defined by a particular set of symptoms that you don't seem to have. You would more likely be considered Asperger's in the old system. The problem with the old system is that it didn't seem to line up with reality. Some people diagnosed with autistic disorder (supposed to be more severe) as a result of a speech delay could grow out of their speech problems and into an Asperger's presentation. Temple Grandin is an example: she had severe speech issues as a child but then outgrew them and essentially is indistinguishable from someone with Asperger's as an adult. And the catch-all PDD-NOS term was actually the most common diagnosis because you had many people who had enough delays to not be diagnosable as Asperger's but not the particular ones that are required for autistic disorder. In addition, it was never conclusively proven that some people with autism truly develop it quickly years after birth or if their symptoms just become obvious to parents who strongly believed initially that they had a typical child- so childhood disintegrative disorder had to be reconsidered as well. Today it would probably be called autism spectrum disorder with possible features of regression, or similar. The system just didn't work as well as intended.
And honestly I am going to just say it: there are forums much better and bigger than teenhelp for discussing autism. You will get much better feedback there. Wrongplanet being one and reddit being another. Wrongplanet has been around for years and is dedicated entirely to autism discussion. The site as a whole is probably still 100 times as busy as teenhelp is in 2024 and all members can relate to some of the same issues.