do you have another charger you can try?
Usually if an iPad wont' charge it's
Bad power brick
bad outlet or
bad imput on your ipad
The first 3 can be diagnosed and user fixed. You diagnose by swapping out the parts. if you replicate the problem, then you eliminate it.
'worst' case scenario is that the port inside your ipad is bad. And if that's the case then you need to make an appointment with your local apple store because that is beyond a user fix. On the upside, if your device is still under warranty and doesn't show any obvious signs of abuse or neglect, then your device will be exchanged for a refurbished replacement.