I would tell myself to not put things off till the last second and just get everything done in the beginning. Appreciate everything that you have because it doesn't get any more simple than high school. Thank Rita for everything she has done to help get you through these last few years, physically, emotionally, and mentally. Don't let you disablility slow you down, you are a bright, talented woman and no one can tell you different. Be yourself.
The number one thing I would go back and tell myself if I could would be to work very hard in college. Studying a lot and putting school first is a big thing because its not as easy as high school was. I would also tell myself to open up to other people and try to make some new friends because being shy doesn't help you to much and you need to find some people to be study buddies with. And also make sure you get enough rest because you need it.