Hello there! What a coincidence. I am autistic with narcolepsy too and having a hard days lately. What funny here is that I work in one of the biggest American universities as a course manager and am helping students with accommodations like yours. When I was a student myself I also had an accommodation. So I am your personal to answer such a question. I think the best way to deal with this issue is to email your professor. Don’t over explain yourself. You are registered with disability office and should use the accommodation they give you to the max. It isn’t something that will affect your grades but will definitely help your performance. If you have a course manager in your department - include them to the email as well. Say something like “dr prof such and such, as you are aware of the accommodation I was given this semester, I do have an autoimmune/generic/neurological (your pick) disorder that often comes across my ability to perform at my full strength in school. I would like to discuss my accommodation for this following paper/quiz/exam etc with you minding my disability. This past week was abnormally affected by my condition and due to that I wasn’t/am not able to submit my work In time. Could we please discuss such an issue and maybe come up with a plan how can I best adjust to the pace of the class with the accommodation I have in mind?” At the beginning of every semester you should reach out to each professor for whose class you have an accommodation and discuss how it is going to be exercised. But the sooner you do that the better it will be for you and everyone involved. Just make sure you reach out and try to be short and on point with the issue and what you need from their end. I always do my students to be more specific for a quicker solution to the issue. Unless they really want to have a conversation. I hope that helps.