Why do I get nasal ulcers? I do have an autoimmune disease.

Many causes. Nasal ulcers can occur due to a variety of things. Nasal sprays, when sprayed on the septum (the divider between l and r halves of the nose) can cause irritation and ulcers. Physical trauma (e.g., nose picking) can cause ulcers. Cocaine will stop blood flow to the lining of the nose, leading to ulcers. Vasculitis can cause bleeding or ulcers. Discuss your symptoms with an otolaryngologist (ent).