In high school everybody tells you what you need to do. Parents and teachers remind you constantly about your responsibilities. Did you do your homework? Do you have your papers? You need to go here and do this and that!!
In college, every professor will give you a syllabus. That is your guideline for your classes. It provides class rules, policies and procedures, calendar of assignments and due dates, and grading policy. In essence, a syllabus tells you exactly what the expectations are of the professor.
EVEN IF THE PROFESSOR DID NOT GO OVER EVERY DETAIL ON THE SYLLABUS, YOU HAVE BEEN TOLD! If you didn't read it and follow up with questions, then you did not do your part. If you take a problem to the dean, in most cases, the first question is going to be "What is on the syllabus?" because the dean needs to know what you were told.
As the student, you will be expected to know all due dates and will be expected to keep track of your grades, tests, and assignments. If you have accommodations, you need to discuss those with the professor. You need to make sure that you are on the same page as the professor when it comes to testing accommodations especially when using a separate testing facility. You will quickly learn which professors need to be reminded about the accommodations, and which ones will always be aware of your needs. Remember, most professors have well over 100 students to deal with, and sometimes they forget something that you might need.