Are the symptoms of mucormycosis bad?

There can be none. "mucor" is actually several different fungi, and infection is almost restricted to people with impaired immunity, e.g. Immunosuppressive drugs, after transplants (bone marrow, or solid organ) or poorly controlled diabetes. When symptoms occur they reflect the organ involved, e.g. The lung, and coughing up blood is common as the bug invades blood vessels. Facial pain can suggest infected sinuses.