Yeah. I didn't think a diagnosis would change as much as it did; I knew I was a scatterbrained introvert, thought I'd made peace with it and found ways to cope. But suddenly with the ADHD+ASD diagnoses, I began to really notice the things that annoyed/drained me. Or, allowed myself to notice.
I don't think I'm less sociable or more exhausted, per se. I just gave myself permission to function on my terms, which includes (but is not limited to) getting irritated by things that I used to not admit to myself irritated me, be a little bit less of a people-pleaser, not ashamed of my excitability, and admit exhaustion in the face of things that "shouldn't" be so exhausting.
In retrospect, it's insane that many people have internalised that medical permission is needed to admit they function better in a personalized (physical/social/cognitive/etc) environment.