Shoot your shot with disability services, get connected with student success/academic advising BEFORE you start struggling, similarly, communicate with your roommate BEFORE any problems and NEVER phrase anything like “because I have X illness Y is going to happen and you have to deal with it”
as a junior who went through college while being diagnosed and is now navigating it with a diagnosis- be honest. with professors do NOT give a sob story and make sure to tell them right at the beginning in a simple email offering to meet if they have any questions. see what therapy/mh services your uni offers and meet with someone in accommodations and explain your situation.