Why won't my iPad charge?

-My iPad died and I plugged it back into the wall outlet with it's correct charger like I always do. I've done this many times before and it always charges somewhat slowly but I am patient, but recently like right now it says 1% then 20 minuets later it says 2% then 30 minuets later it says 1% again?! This is really pissing me off! I got it for Christmas and it is not damaged in any way as far as I know. Is this happening to anyone else or am I alone? Does anyone have any idea what might be wrong with my iPad? Is it built up dust in the charging hole and/or the battery? Please help if you can.