If it isn't charging you either have a charger problem, a port problem or a battery problem.
I would see if you can try your charger on another device, and another charger on your device, to see if your charger works on a different one and also to see if the other one charges yours. If the cord charges the other device, then it isn't the cord. If a different cord charges yours, then it isn't the port. However, if you try a cord you know works on a different device, but doesn't work on yours, it is possibly the port that is damaged.
Before you jump and get it fixed/replaced, first check your battery. You can get new ones pretty cheaply. If the battery is good, then it is likely the port, which will usually be attached to the...