I got a bite on my hand 5 days ago. Today my neck is stiff, my hand is still swollen, my hand hurts and yellow pus is coming out of my hand?

Treatment needed now. A hand bite can become a severe infection. If there are any signs of infection, antibiotic treatment is needed. For a bad infection or a rapidly progressing one, hospitalization for I.V. Antibiotics and/or surgery may be needed.
See a doctor! From your description you have an infection. These can become very serious very quickly. You should seek medical attention as soon as possible.