Being a bad boss, or a belligerent jerk, isn't actionable, even if they aren't admirable character traits in a supervisor.

You have been invited to follow company procedure in relation to your complaints, and have chosen not to do so. Your failure to follow procedure, and to properly document complaints within the company, could impair any cause of action you might have.

If you do need to be accommodated because of disability, you need to request accommodation. If you have informed your employer of your disability, that's a good first step, but if you have not indicated that you are having difficulty performing your job due to your disability and that you require reasonable accommodation, they won't know that you need that help.

If you believe you have been denied leave for work-related illness in violation of your state's laws, you should consider consulting with a local workers' compensation lawyer about that problem.