I got myself a single room at my University for the same reason, the idea of sharing a room with a complete stranger was a big no no for me. I do think that single rooms are on a first come first serve basis, so move on them as quickly as you can. Having a diagnostic could also help out with requiring a single room, so be sure to submit all the necessary paperwork to your college's disability services (I imagine that every college campus should have one at this point). Also be aware that a single will cost more than the traditional shared double, but for the comfort of having a space all to yourself, I think it is worth it.
I don't know what the singles at the college you will be attending are like, but they may vary from school to school. The singles one college I looked at had four single rooms that shared one common room while the university I am attending has the 'traditional' single where it is just your room and nothing else. So be sure to actually see the dorm buildings so you can get an idea of what they are like. My single room is quite nice with a decent amount of space and 12ft high ceilings, and to top it off for my personal appeal, it is in a building built in the 1880's so the architecture is wonderful.
Best of luck in college, hope I've helped, and enjoy your time there! 