Does anaphylaxis usually cause many symptoms?

Yes. Anaphylaxis is a serious allergic reaction. Symptoms develop quickly [seconds to minutes] after a person is exposed to something he or she is allergic to [foods, medications, insect bites, etc]. Symptoms can include hives [itchy, raised, red patches], trouble breathing/swallowing, wheezing, abdominal pain/cramping. Prompt treatment can be life saving. Use an epi-pen if you have it. Then er.
Yes. Anaphylaxis is a severe form of allergic response. It usually results in multiple often very severe symptoms such as cough, wheeze, shortness of breath, low blood pressure, loss of consciousness or even death.
Anaphylaxis symptoms. Anaphylaxis is a term used to describe an acute, severe allergic reaction, typically affecting several organ systems. Areas affected can include the skin (itching, rash, swelling), respiratory tract (throat closing, shortness of breath, wheezing, chest tightness), GI tract (nausea, vomiting, abdominal pain, diarrhea), cardiovascular system (chest pain, palpitations, low blood pressure, dizziness).