why are people so quick to judge?

Well first impressions are just things we don't control, we make them judging by past experience and logical thinking comes only after that, so basically we are a evil community of animals, but not to worry, you can change everything, at least making yourself feel better, when someone misjudges you, don't pay attention, look at it with humor, remember that the person that made that mistake is a non-educated idiot and move on, I used to leave awful first impressions wherever I went (just a bad mojo I guess), I can't say I know how you feel, since I am not in a wheelchair, but the main idea stays the same. All the biggest problems in life are actually simple and easy to overcome if you find the right perspective. I am guessing you have your friends and family that support you and support combined with love is the best medicine out there, you will overcome this problem with ease :) One more suggestion- stop worrying about what others think, do what you want where you want to :)