There are several comments stating that HSP is not a thing, that it is Autism instead. While this is important to highlight, I disagree with this assessment - there IS a thing as HSP, which is different to Autism.
I'm a HSP, I was married to an Autistic woman for 11 years (now separated) so I feel I have a good basis for comparison. In my experience, there are some overlaps between the HSP and Autistic experience, but the main difference is the depth of the feelings, challenges, experiences etc. For example, when my ex-wife would get overwhelmed and burned out (a very regular occurrence when working in a busy, noisy office environment for example), it would take her several days of rest and quiet to reset. But for myself, the same noisy and busy environment would require a few hours of rest and quiet.
So for anyone questioning whether they are HSP or Autistic, my advice is to consider the depth of the feelings, challenges and experiences you are having - if these are really affecting you life in a big way and a struggle to manage every day, it's probably Autism, but if these are just something you easily manage, it's probably HSP.