An allergy.
An overreaction of the immune system to an otherwise harmless substance is called an allergic reaction. In allergies, the immune system mistakenly identifies the harmless substance as a threat and produces an exaggerated response, leading to symptoms such as sneezing, itching, or hives.
The Immune Disorder SLE is and autoimmune disorder.
Yes Rheumatoid arthritis is an immune system disorder in which the immune system turns on the body and mistakenly destroys tissue.
Several diseases are caused by immune disorders. Alopecia - where the hair falls out in clumps - may well be caused by an immune disorder.
Allergy
Any disorder affecting immunity is called as immune system disorder. Now most common cause for the same is HIV infection.
Vaccines contain a 'dead' or weakened form of a virus. The immune system will still respond as if the virus were a threat (when it is completely harmless) and will destroy it, generating lymphocytes that will 'recognise' the virus if it ever enters the body again, allowing rapid destruction if the virus ever enters the body again.
Allergy
yes
That is called an allergy.
lymph
their immune system is ruined