Theresa,
I'll bet your discipline is something from the math or science field (that is, YOUR major was in one of those fields as an undergraduate, right?). Folks who come from such a background are most comfortable in dealing with right and wrong answers. There is no "gray area" in doing a math problem. But working with students with disabilities is full of "gray areas." If you can get comfortable with the idea that it is alright to work with (and around) options to standard procedures, you'll do fine -- and so will your students!
Dr. Jane Jarrow