charging problem of ipod touch 5g

I never had a charging problem with my iPod touch 5g until i accidentally super drain it. when i charged it, it didnt charge at all. almost everyday, i tried to charge with no luck and no display. After a week, i tried one more time, viola! it charged but only 89%.. My problem now is that when i charged it for almost 24 hours it still remains 12%.. it reaches 29% then back to 12%.. I tried charging it directly to the power source, in my netbook and even using power bank, still battery remains 12 -15% only. Can anyone help me what to do?