I would recommend a couple of things before you take drastic measures:
-Be sure you are using the charger that CAME with your phone. Sometimes if you use a generic charger, it will fail to charge.
-Be sure the outlet you are using isn't faulty, try a couple different ones.
-Try plugging the phone into the computer to see if it begins to charge.
If none of those have any impact, unfortunately, you will need to bring the phone back to wherever you purchased it, as it is a faulty device.