How to treat newly infected earlobe piercing?

Antibiotics are the only way to get rid of an infection (the solution they gave you likely prevents infections, not treats them). Go to a local pharmacy and buy some neosporin or other antibiotic gel and apply it as described in the instructions. This should heal it up right away. If it doesn't you may have to go to the doctor for some stronger or more directed prescription antibiotics. The sooner you treat it with antibiotics, the less complications there will be with the piercing, so take off for the store right now! :P