I've had a couple time when people were rather annoyed at the time i took, but usually after they see me (my head is all messed up from accident) and the wheelchair they usually say sorry, or something. Only once did i ever NOT get a sorry after someone knocking on the door.
I also these days am usually with my PCA so, when they see me being pused out and a helper with they really say sorry as they at that point recognize that its more than just getting on the toilet. I have to not only deal with the wheelchair, but also my back brace, diapers one bad leg and a not so good arm. Its not easy gettin on/off the chair as it is, and usually there are enough rails to get it done, but changing a diaper on a full size 250# person when my leg wont cooperate isnt very quick, tis i try to just do at home or even in the van is better. But i have found that the van harness i have does help the PCA to lift/help me getting around quite a bit and just leave it on when im out to use for getting in/out of the van and the wheelchair.
Basically what i comes down to is people are clueless and dont care about anything but thier own self.
Like, yes i have lumps and bumps on my head and also in a wheelchair with a harness and feet, but i've gotten a few times people trying to talk to me vey slow and loud, which i usually say, My body is broken but my Mind is just fine, what can i help you with.
You should have asked the person knocking if they want to come in and help you out. Or similar, Usually when you call people on beig dumb/idiots they get the point. Or when you came out, if she said more, should have said, oops forgot something and went back in there...make her wait more
But, usually if you call people on the stupid things they do, they might learn something, dont have to be mean, just let them know the world doesnt revolve around them.
If you see that person at that place again, every time she goes in the bathrrom immediatly go knock on the door and ask her if she is done yet...
Really if someone is impatient like that, I have had the PCA go talk to them, explain to them that i'm disabled and need help, and the time the PCA is talking to them is waisting time which will cause it to be longer as long as they are out talking to the person.
My one PCA from a few years back used to answer the door, and was a pretty confident spitfire of 5' tall 100lbs, and she would call them out immediatly...Nothig mean, Just explain that she is my Personal Care Assistant and she is there to help me with my needs, and her taking the time to talk to the person knocking at the door is causing me to wait till she can get back in the bathroom to continue to help me with my needs before the bathroom will be free.
She would be nice about it, untill someone was NOT nice to her or me and then she would lay into them very much.
But, sorry you and i think everyone has to deal with this, but there is nothing wrong in explaining to them the siuation and perhaps they will learn something.
Or maybe they would take up the "come in and help" offer, preferabbly with dealing with a messy diaper, they would learn rather quickly at that point