While understandable, I hope you might value something in my experience being "the daughter". First up; my disability is physical and hard to miss unless your legally blind (and even then, it will get noticed by for instance the sounds my aids make etc.
).
My mom is what I call overprotectice and oversensitive. She notices each and all stares, look, comments, judgements or even just things people are thinking that might not be positive. She kinda is like you; she shows her noticing it and it getting her upset. And you know what? It bugs the hell out of me! First of all; by doing this she will make me aware of things out there that I myself am not aware of as either I'm too busy with something else or because I have built in beter coping skills than she has. It is a shame to notice each and every time that she still focusses on the negatives and let those determine how she acts or not and yes; how it can thus influence me also. She's entitled to her own emotions and we all know any parent would go to bat for their child, but there should be a balance in there IMHO.
For instance, when at WDW? I will be way to busy enjoying myself to notice about 99% of things that might not be the most positive. My mom on the other hand? Sees it all! Worries about it all. Her day will consist of those 2 comments while using the bus, 3 looks at rides where we used alternate lines/waitingareas and those 8 folks that jumped in front of my powerchair in such a way it became unsafe. My day will have been that bus that came just as we walk up to the busstop, those 3 CM's we had a nice chat with, those guests we had a nice interaction with, that one ride I rode, those magical small moments/views we ran into while navigating the park, those laughs we had about silly things, the story about how we ran into the perfect souvenir for dad etc. And by the end of the day; telling myself to count to 10 (or more), take a sigh, and politely asking my mom to not be so in my face with her own sentiment about how others might react to me in a way she considered "done me wrong".
I'm not saying, nor would I ever, that you can not have your own sentiments about this or respond to them and for instance advocate for their child when needed and the child can not do that. I'm just saying; be aware of how your OWN behaviour and outlook on these things can influence your DD, both in the way she reacts to it and the way she feels about herself. Sometimes it can influence more than the incident it started out with. Best thing for BOTH of you is to learn to find a balance in this. You will never even come close to getting rid of any and all stares, comments and what not. So start with giving up that illusion, it'll save you a lot. Where possible ignore. Focus on other stuff going on at that moment. Esp. if DD is not aware of it; stay in her world and enjoy her focus. If she's happy and content, watching that moment through her eyes and seeing her focus will make you feel a heck of a lot better than through the protectice dad glasses will.
Humor can do a lot. Both for yourself in making it easier to deal with, but also when it comes to accidently educating an outsider when they're open to it. Same goes for a smile, politeness etc. Much easier to get your message across than anger, lecturing or whatever.
Realise that you can not change the outside world or others. You can however influence how you deal with them and can teach your own daughter the same. Teaching by example is the most powerfull way to do so.
In those -still very- rare situations where it really gets dangerous; get daughter out of the danger zone. Take a breath, rant if need be (if emotions run too high, don't show those in front of daughter), if possible learn from the situation and talk it over with daughter in a way that is on her level.
As a parent you know you will have to teach your child/children how they can keep themselves standing in the real world. Prepare and guide them over the years so they can be as independant and healthy as possible in each and every way. When you become a parent of a child with a special need, you then also need to some of this for yourself. How do you do this while respecting the needs your child has but also in a way that still makes sure the child can thrive and is possible to get the best out of themselves? Educating yourselfs in how to deal with the outside worlds reaction to your daugther is one of the many courses you will need to take yourself. It doesn't all come in one lesson, it takes many of them. You will grow and learn. Make sure you keep your goal in mind (raising a as balanced as possible child that feels secure, safe and stabile that has the tools to make the most out of her life as she can) and set your curriculum accordingly. Sometimes you will find there are surprise tests like you had the other day. You took the test. How would you grade it when keeping the goals in mind? Where could you improve? How can you work on that? What is already going well and also deserves noticing?
And always remember; people will always think all kinds of things about you and loved ones and judge, even when there is nothing to think or judge. You can not stop that, so never let it stop you from doing anything.
