There should be some normal swelling after a piercing that can easily be dealt with by taking ibuprofen, putting ice on it, and drinking a lot of water. If there is oozing a yellow or white liquid, crusties, a foul smell ETC there could be an infection and you should see a doctor about an antibiotic treatment. Clean your piercing by gently washing away the crusties with saline solution, or put your earlobe into a cup of saline solution to soak for 5 minutes. Don't touch a fresh piercing unless you are cleaning it, and always wash your hands before you do. If you have any significant problems where you may feel you have to remove the piercing, make sure you talk to your piercer first as this may not always be necessary. Talking to your doctor and professional piercer are important and they are the best people to go to for this sort of problem.