I’m 51 and I was recently diagnosed as well. My story is incredibly similar to yours (especially the grocery store part and the wanting to scream in meetings part). I don’t work with children, but I have an Aspie nephew.
The only reason I sought an official diagnosis is because I was having ADHD related trouble at work and was afraid of losing my job. I believe that the grief I experienced over the loss of my dad triggered increased inattentive behavior to the point where my usual “work-arounds” were not working. Once I got the diagnosis and was put on Ritalin (and now Concerta), I feel more “normal” than I ever have.
I can follow my own train of thought when I’m running my mouth, which is huge for me. It was always so frustrating to be in the middle of telling someone something and go off on a tangent and not be able to get back to the original topic because I couldn’t remember what it was.
I can concentrate when people at work are explaining things to me, and I’m actually getting it now. Before, I was too busy thinking about how I would not get it, even before the person was finished.
And I could go on and on about the little things that have improved for me since then.
So, in answer to your question, from my point of view, the benefit to getting an official diagnosis, even if you don’t plan to take medication right now, is that if something happens to you like what happened to me, it would be easier and faster for you to get the medication if you already had an established diagnosis.
But really, unless the ADHD symptoms are causing real problems for you, there is no benefit to getting the diagnosis except for maybe some peace of mind for you. Which actually could be a huge benefit. It’s completely up to you. 