You will have some slight swelling and tenderness around the site of a body piercing. This is expected. Gradual swelling that develops slowly over 6 to 12 hours or longer usually does not indicate a severe problem. In most cases, home treatment is all that is needed to reduce swelling and discomfort.
Piercing with a large needle can damage larger blood vessels, nerves, and other deep tissues. Rapid swelling immediately after a piercing may indicate bleeding or an injury that has caused deep tissue damage.
WebMD Medical Reference from Healthwise