MS and the 'disabled' label

As someone who has MS it will probably come as no surprise to you that I am in possession of the ubiquitous blue badge. I applied for it for various reasons but the main ones include being able to have close access to shops and when my bladder is at its worst, a toilet.
When I go shopping I always plan my shopping route in advance so that I can complete all of my chores without walking too far unnecessarily or doubling back on myself - thus reducing the pain in my feet.
And it's a running joke with my mum that I know every bathroom in Derry (and I may add, every other town or city I have ever visited, thanks to my good memory for such information).
But using the blue badge is not something I enjoy or have become comfortable with.
It sound silly but I always feel that people who don't know me stare when I get out of my car looking, to them, perfectly healthy. There's no wheelchair or stick - and to many that means I'm not disabled as the badge suggests.
I guess it's an education exercise but disabled means so much more than not being able to walk unaided.
Recently I got into my car and was about to reverse out of the space when a man stood behind me waving a disabled badge. Naively I believed he simply wanted the space after me and was claiming it as his own before anyone on the busy road drove in after me.
But, as I reversed he shouted over, 'You know you're parked in a disabled space?' - with a tone that implied that he didn't feel I should be there. I instantly leaned over, waved by own badge back at him and replied, 'Yes, I have MS if you must know'.
The incident really shook me up. He was aggressive and frankly, rude. To his mind, he had seen a happy, healthy looking young woman walk up to her car with some friends and promptly drive away. He obviously hadn't bothered to check I had a badge displayed and jumped to his own, wrong, conclusions.
This sort of attitude is hard to change. And for someone like me who hates being labelled 'disabled' anyway, it just made me feel about two feet tall.
I don't expect everyone to understand what it's like to have an illness like Multiple Sclerosis but I certainly think that a touch of compassion now and again wouldn't go amiss.
As for judging me without knowing me, that's another issue altogether and one I'll talk about further another day.